CVE-2025-3500: Avast Antivirus

Critical severity, CVSS 9.8. EPSS: 0.5% chance of exploitation in the next 30 days.

Integer Overflow or Wraparound vulnerability in Avast Antivirus (25.1.981.6) on Windows allows Privilege Escalation.This issue affects Antivirus: from 25.1.981.6 before 25.3.

Affected products

• Avast Antivirus: from 25.1.981.6, before 25.3 (fixed in 25.3)

Published 2025-12-01. Last modified 2026-09-26.