CVE-2021-45336: Avast Antivirus

High severity, CVSS 8.8. EPSS: 0.5% chance of exploitation in the next 30 days.

Privilege escalation vulnerability in the Sandbox component of Avast Antivirus prior to 20.4 allows a local sandboxed code to gain elevated privileges by using system IPC interfaces which could lead to exit the sandbox and acquire SYSTEM privileges.

Affected products

• Avast Antivirus: before 20.4 (fixed in 20.4)

Published 2021-12-27. Last modified 2026-06-17.