Use of stack memory after free vulnerability in Avast Antivirus when scanning a malformed Windows PE file may allow Denial-of-Service of the antivirus process.
This issue affects Avast Antivirus, AVG Antivirus, Norton Antivirus, Avast One, and Avast Business Antivirus on Windows, macOS, and Linux for virus definition builds before VPS 25022500.
The affected scanning logic is delivered through a shared Gen Digital virus definition update stream. The same stream feeds the consumer antivirus products listed in this advisory and other Gen Digital products that embed the same engine. Mitigation flows through this update channel; installations at or above the listed build are not vulnerable regardless of which product consumes the stream.
Install virus definitions VPS 25022500 or any later virus-definition update. All builds at or above VPS 25022500 include the fix; staying current on definitions is required.