CVE-2006-4626: Alwil Avast Antivirus

High severity, CVSS 7.5. EPSS: 4.8% chance of exploitation in the next 30 days.

Heap-based buffer overflow in alwil avast! Anti-virus Engine before 4.7.869 allows remote attackers to execute arbitrary code via a crafted LHA file that contains extended headers with file and directory names whose concatenation triggers the overflow.

Affected products

• Alwil Avast Antivirus: up to and including 4.6.460; up to and including 4.6.763; version 4.0.168 only; version 4.0.172 only; version 4.0.183 only; version 4.0.202 only; …

Published 2006-09-07. Last modified 2026-06-16.