Compromised Chromium Extensions Push Malware Through Fake Critical Update Alerts

Users of Chromium-based browsers including Chrome, Brave, and Opera have encountered persistent pop-up windows demanding immediate browser updates. These alerts originate from compromised extensions that dynamically load malicious VBS scripts or EXE files instead of delivering legitimate updates. The deceptive messages appear during normal browsing and instruct users to download and manually execute suspicious files. Earlier incidents were traced to the QuickLens extension, while current reports implicate Enable Right Click & Copy Smart Unlock + OCR and similar utilities still available in the Chrome Web Store. Attackers achieve persistence by purchasing popular extensions or hijacking developer accounts to push malicious updates. Full system scans often fail to detect the threat because the browser itself remains clean until the user triggers the payload. Security experts recommend verifying updates exclusively through the browser's built-in menu rather than clicking any on-screen prompts.

AntiMalwareTranslated from Russian

Read at source

Users of Chromium-based browsers have reported intrusive pop-up notifications claiming that a Critical Update Required or Update available must be installed immediately. These messages appear while browsing regular websites and, when clicked, deliver either a VBS script or an EXE file that the user must run manually.

The problem affects not only Chrome but also Brave and Opera, with the fake alerts incorrectly suggesting an update for Google Chrome. The inconsistency in the update text quickly reveals the deception to attentive users.

The source of the malicious windows is compromised browser extensions that fetch harmful scripts from external servers at runtime. Because the dangerous code is not stored inside the extension package itself, conventional antivirus scans frequently return clean results until the user interacts with the prompt.

Earlier campaigns were linked to the extension QuickLens — Search Screen with Google Lens, which was later removed from the Chrome Web Store. Recent reports point to Enable Right Click & Copy Smart Unlock + OCR and other small utilities that remain available, some with tens of thousands of installations and high user ratings.

Attackers typically obtain control by purchasing a popular legitimate extension or compromising the developer account, after which they publish an update containing the new malicious behavior. Security researchers advise users never to download or execute files offered through such pop-ups and to check for genuine browser updates only via the built-in settings menu.

Meridian digestThe week's most consequential security stories, distilled into one briefing.See the digest

More in Malware & Botnets

Yoba Campaign Uses Signed ChatGPT and Claude Binaries for DLL Sideloading and XMRig Deployment
uCreator Spyware Infiltrates Modified Telegram, WeChat and GCash Builds on Android
Researchers Deploy Cowrie Honeypot Disguised as NVIDIA H100 Server to Study SSH Botnet Tactics