Description
The ENSURE_BITS macro in mszipd.c for Clam AntiVirus (ClamAV) 0.83, and other versions vefore 0.86, allows remote attackers to cause a denial of service (CPU consumption by infinite loop) via a cabinet (CAB) file with the cffile_FolderOffset field set to 0xff, which causes a zero-length read.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗Advisories 2
- DSA-737-1 clamav - various DOS vulnerabilities Debian Security (DSA / DLA) · Mar 9, 2026
- DTSA-3-1 clamav - denial of service and privilege escalation Debian Security (DSA / DLA) · Mar 9, 2026
References
- 20050629 Clam AntiVirus ClamAV Cabinet File Handling DoS Vulnerability third-party-advisory
- DSA-737 vendor-advisory