CVE-2023-20212

What it actually does

Logic error in AutoIt module memory management allows a crafted file submission to trigger an unexpected restart of the ClamAV scanning process.

Why it matters to the business

Scanning services become intermittently unavailable, delaying malware detection and potentially exposing systems to unfiltered threats during restarts.

How an attack unfolds

An attacker crafts a malicious AutoIt file and submits it for scanning by ClamAV; the memory management flaw causes the scanner to restart, achieving denial of service without authentication.

How to fix it

Upgrade affected ClamAV installations to a version containing the memory management fix; monitor vendor advisories for the exact patch release after 2023-08-18.

How to confirm the fix worked

Submit known test AutoIt files that previously triggered restarts; confirm the scanning process remains stable and review release notes for the memory management correction.

Typical attack path

1. Identify a reachable ClamAV instance accepting file scans
2. Prepare and submit a specially crafted AutoIt file
3. Trigger the memory logic error during parsing
4. Observe repeated scanning process restarts

How to detect it

Review ClamAV process logs and system event logs for repeated unexpected restarts correlated with AutoIt file scan entries; look for spikes in file submissions immediately preceding crashes.

What your security team should do

• Prioritize patching ClamAV instances exposed to untrusted file uploads within the next 30 days
• Implement file-type filtering or sandboxing for AutoIt submissions until patched
• Enable process monitoring and automatic restart alerts for the ClamAV daemon