Exploited Windows zero-day lets JavaScript files bypass security warnings

An update was added to the end of the article explaining that any Authenticode-signed file, including executables, can be modified to bypass warnings.

A new Windows zero-day allows threat actors to use malicious stand-alone JavaScript files to bypass Mark-of-the-Web security warnings. Threat actors are already seen using the zero-day bug in ransomware attacks.

Windows includes a security feature called Mark-of-the-Web (MoTW) that flags a file as having been downloaded from the Internet and, therefore, should be treated with caution as it could be malicious.

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Source: Bleeping Computer