CVE-2008-5521: Free-AV Antivir

High severity, CVSS 9.3. EPSS: 1.9% chance of exploitation in the next 30 days.

Avira AntiVir 7.9.0.36 and possibly 7.8.1.28, when Internet Explorer 6 or 7 is used, allows remote attackers to bypass detection of malware in an HTML document by placing an MZ header (aka "EXE info") at the beginning, and modifying the filename to have (1) no extension, (2) a .txt extension, or (3) a .jpg extension, as demonstrated by a document containing a CVE-2006-5745 exploit.

Affected products

• Free-AV Antivir: version 7.8.1.28 only; version 7.9.0.36 only

Published 2008-12-12. Last modified 2026-06-16.