CVE-2026-20338
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk25th percentile - higher than 25% of all known CVEs
Summary
A vulnerability in the zip archive parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition. The issue is due to improper memory handling when processing zip files during scanning. An attacker could exploit this by submitting a crafted zip file for scanning.
Risk Assessment
Successful exploitation could cause the ClamAV scanning process to terminate due to a memory double-free, resulting in a denial of service (DoS). This could prevent scanning of archives and expose the system to threats.
Recommendation
It is recommended to update ClamAV to a patched version. Also consider restricting access to scanning services and monitoring for unusual zip files.
Other vulnerabilities in ClamAV
See all- CVE-2015-1462High
ClamAV before 0.98.6 allows remote attackers to have unspecified impact via a crafted upx packer file, related to a 'heap out of bounds condition.'
- CVE-2015-1461High
ClamAV before 0.98.6 allows remote attackers to have unspecified impact via a crafted Yoda's crypter or mew packer file, related to a 'heap out of bounds condition.'
- CVE-2014-9328High
ClamAV before 0.98.6 allows remote attackers to have unspecified impact via a crafted upack packer file, related to a 'heap out of bounds condition.'
- CVE-2026-20348High
A vulnerability in the XAR file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition or possibly other expanded impacts as a result of memory corruption. This is due to improper boundary checks for content in XAR files during scanning.
- CVE-2026-20347High
A vulnerability in the Mach-O file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition or possibly other expanded impacts as a result of memory corruption. This is due to improper boundary checks, which may result in an out-of-bounds buffer read.
- CVE-2026-20346High
A vulnerability in the PDF file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition or possibly other expanded impacts as a result of memory corruption. This is due to improper boundary checks, which may result in an out-of-bounds buffer read.
- CVE-2026-20345High
A vulnerability in the GPT file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition or possibly other expanded impacts as a result of memory corruption. This is due to improper handling of an endian conversion operation, which may result in an out-of-bounds buffer write.
- CVE-2026-20339High
A vulnerability in the PESpin file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition or possibly other impacts due to memory corruption. The issue is caused by improper boundary checks in PESpin files during scanning, which may result in an integer overflow. An attacker could exploit this by submitting a crafted file with PESpin content to be scanned by ClamAV.
- CVE-2026-20337High
A vulnerability in the zip archive parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition. The issue is due to improper boundary checks for zip file content during scanning, which may result in an out-of-bounds write. An attacker could exploit this by submitting a crafted zip file for scanning.
- CVE-2026-20244High
A vulnerability in the DMG file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition or other impacts from memory corruption. The issue is due to improper boundary checks in DMG scanning, leading to integer overflow on 32-bit platforms only.
Original NVD description (English source)
A vulnerability in the zip archive parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition on an affected device. This vulnerability is due to improper memory handling when processing content in zip files during scanning. An attacker could exploit this vulnerability by submitting a crafted zip file for scanning. A successful exploit could allow the attacker to cause the ClamAV scanning process to terminate as a result of a memory double-free, resulting in a DoS condition on the affected software.