WhatsApp is going through a rough patch. Some users would argue it has been ever since Meta acquired the once widely trusted messaging platform. User sentiment has shifted from “trusted default messenger” to a grudgingly necessary Meta product.

Privacy-aware users still see WhatsApp as one of the more secure mass-market messaging platforms if you lock down its settings. Even then, many remain uneasy about Meta’s broader ecosystem, and wish all their contacts would switch to a more secure platform.

Back to current affairs, which will only reinforce that sentiment.

Google’s Project Zero has just disclosed a WhatsApp vulnerability where a malicious media file, sent into a newly created group chat, can be automatically downloaded and used as an attack vector.

The bug affects WhatsApp on Android and involves zero‑click media downloads in group chats. You can be attacked simply by being added to a group and having a malicious file sent to you.

According to Project Zero, the attack is most likely to be used in targeted campaigns, since the attacker needs to know or guess at least one contact. While focused, it is relatively easy to repeat once an attacker has a likely target list.

And to put a cherry on top for WhatsApp’s competitors, a potentially even more serious concern for the popular messaging platform, an international group of plaintiffs sued Meta Platforms, alleging the WhatsApp owner can store, analyze, and access virtually all of users’ private communications, despite WhatsApp’s end-to-end encryption claims.

How to secure WhatsApp

Reportedly, Meta pushed a server change on November 11, 2025, but Google says that only partially resolved the issue. So, Meta is working on a comprehensive fix.

Google’s advice is to disable Automatic Download or enable WhatsApp’s Advanced Privacy Mode so that media is not automatically downloaded to your phone.

And you’ll need to keep WhatsApp updated to get the latest patches, which is true for any app and for Android itself.

Turn off auto-download of media

Goal: ensure that no photos, videos, audio, or documents are pulled to the device without an explicit decision.

• Open WhatsApp on your Android device.
• Tap the three‑dot menu in the top‑right corner, then tap Settings.
• Go to Storage and data (sometimes labeled Data and storage usage).
• Under Media auto-download, you will see When using mobile data, when connected on Wi‑Fi. and when roaming.
• For each of these three entries, tap it and uncheck all media types: Photos, Audio, Videos, Documents. Then tap OK.
• Confirm that each category now shows something like “No media” under it.

Doing this directly implements Project Zero’s guidance to “disable Automatic Download” so that malicious media can’t silently land on your storage as soon as you are dropped into a hostile group.

Stop WhatsApp from saving media to your Android gallery

Even if WhatsApp still downloads some content, you can stop it from leaking into shared storage where other apps and system components see it.

• In Settings, go to Chats.
• Turn off Media visibility (or similar option such as Show media in gallery). For particularly sensitive chats, open the chat, tap the contact or group name, find Media visibility, and set it to No for that thread.

WhatsApp is a sandbox, and should contain the threat. Which means, keeping media inside WhatsApp makes it harder for a malicious file to be processed by other, possibly more vulnerable components.

Lock down who can add you to groups

The attack chain requires the attacker to add you and one of your contacts to a new group. Reducing who can do that lowers risk.

• ​In Settings, tap Privacy.
• Tap Groups.
• Change from Everyone to My contacts or ideally My contacts except… and exclude any numbers you do not fully trust.
• If you use WhatsApp for work, consider keeping group membership strictly to known contacts and approved admins.

Set up two-step verification on your WhatsApp account

Read this guide for Android and iOS to learn how to do that.

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We don’t just report on phone security—we provide it

Cybersecurity risks should never spread beyond a headline. Keep threats off your mobile devices by downloading Malwarebytes for iOS, and Malwarebytes for Android today.

This blog is part of a series highlighting new and concerning trends we noticed over the last year. Trends matter because they almost always provide a good indication of what’s coming next.

If there’s one thing that became very clear in 2025, it’s that malware is no longer focused on Windows alone. We’ve seen some major developments, especially in campaigns targeting Android and macOS. Unfortunately, many people still don’t realize that protecting smartphones, tablets, and other connected devices is just as essential as securing their laptops.

Android

Banking Trojans on Android are not new, but their level of sophistication continues to rise. These threats continue to be a major problem in 2025, often disguising themselves as fake apps to steal credentials or stealthily take over devices. A recent wave of advanced banking Trojans, such as Herodotus, can mimic human typing behaviors to evade detection, highlighting just how refined these attacks have become. Android malware also includes adware that aggressively pushes intrusive ads through free apps, degrading both the user experience and overall security.

Several Trojans were found to use overlays, which are fake login screens appearing on top of real banking and cryptocurrency apps. They can read what’s on the screen, so when someone enters their username and password, the malware steals them.

macOS

One of the most notable developments for Mac users was the expansion of the notorious ClickFix campaign to macOS. Early in 2025, I described how criminals used fake CAPTCHA sites and a clipboard hijacker to provide instructions that led visitors ro infect their own machines with the Lumma infostealer.

ClickFix is the name researchers have since given to this type of campaign, where users are tricked into running malicious commands themselves. On macOS, this technique is being used to distribute both AMOS stealers and the Rhadamanthys infostealer.

Cross-platform

Malware developers increasingly use cross-platform languages such as Rust and Go to create malware that can run on Windows, macOS, Linux, mobile, and even Internet of Things (IoT) devices. This enables flexible targeting and expands the number of potential victims. Malware-as-a-Service (MaaS) models are on the rise, offering these tools for rent or purchase on underground markets, further professionalizing malware development and distribution.

Social engineering

iPhone users have been found to be more prone to scams and less conscious about mobile security than Android owners. That brings us to the first line of defense, which has nothing to do with the device or operating system you use: education.

Social engineering exploits human behavior, and knowing what to look out for makes you far less likely to fall for a scam.

Fake apps that turn out to be malware, malicious apps in the Play Store, sextortion, and costly romance scams all prey on basic human emotions. They either go straight for the money or deliver Trojan droppers as the first step toward infecting a device.

We’ve also seen consistent growth in Remote Access Trojan (RAT) activity, often used as an initial infection method. There’s also been a rise in finance-focused attacks, including cryptocurrency and banking-related targets, alongside widespread stealer malware driving data breaches.

What does this mean for 2026?

Taken together, these trends point to a clear shift. Cybercriminals are increasingly focusing on operating systems beyond Windows, combining advanced techniques and social engineering tailored specifically to mobile and macOS.

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We don’t just report on threats—we remove them

Cybersecurity risks should never spread beyond a headline. Keep threats off your devices by downloading Malwarebytes today.