CVE-2023-20032

What it actually does

Missing buffer size check in HFS+ partition file parser results in heap buffer overflow write, enabling arbitrary code execution or process crash.

Why it matters to the business

Attackers can run malicious code on systems using the scanning library or disrupt file scanning operations, affecting malware detection and availability.

How an attack unfolds

An attacker crafts a malicious HFS+ partition file and submits it for scanning; the missing check triggers a heap overflow that allows code execution with the scanner's privileges or causes a denial of service.

How to fix it

Upgrade ClamAV to a fixed version beyond 1.0.0, 0.105.1, or 0.103.7 depending on the branch in use.

How to confirm the fix worked

Verify the installed ClamAV version against fixed releases and test scanning of known-good versus crafted sample files for stability.

Typical attack path

1. Craft malicious HFS+ partition file exploiting missing buffer check
2. Submit the file to ClamAV for scanning via network or local interface
3. Trigger heap buffer overflow to execute arbitrary code or crash the process

How to detect it

Inspect ClamAV process logs and system crash reports for unexpected terminations or anomalous memory activity during file scans.

What your security team should do

• Apply the appropriate ClamAV update immediately across all instances
• Review and restrict file submission sources to trusted inputs where feasible
• Monitor process behavior for unexpected crashes or privilege escalations