Compromised Chromium Extensions Push Malware Through Fake Critical Update Alerts
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.
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