Overview

During a recent malware cleanup investigation, we encountered a compromised Joomla website where the site owner reported a strange issue. Their website displayed a large number of suspicious product links that had nothing to do with their business. These products were not added by the website owner and did not exist in their catalog.

Visitors and search engines were seeing pages that promoted unrelated products, raising immediate concerns about spam injection or remote content manipulation.

Continue reading Joomla SEO Spam Injector: Obfuscated PHP Backdoor Hijacking Site Visitors at Sucuri Blog.

Web shells are malicious scripts that give attackers persistent access to compromised web servers, enabling them to execute commands and control the server remotely. These scripts exploit vulnerabilities like SQL injection, remote file inclusion (RFI), and cross-site scripting (XSS) to gain entry.

Once deployed, web shells allow attackers to manipulate the server, leading to data theft, website defacement, or serving as a launchpad for further attacks. They are especially dangerous because they are also a post-compromise access mechanism (backdoor) rather than a standalone infection.

Continue reading Web Shells: Types, Mitigation & Removal at Sucuri Blog.