CVE-2026-20337: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') in Cisco Cisco Secure Endpoint
A vulnerability in the zip archive parser of ClamAV allows an unauthenticated remote attacker to cause a denial-of-service (DoS) condition by submitting a specially crafted zip file. The flaw arises from improper boundary checks during zip file scanning, leading to an out-of-bounds write that terminates the scanning process.
AI Analysis
Technical Summary
CVE-2026-20337 is a high-severity vulnerability in ClamAV's zip archive parser caused by improper boundary checks on zip file content during scanning. This results in an out-of-bounds write condition that can be triggered by an unauthenticated remote attacker submitting a maliciously crafted zip file. Exploitation causes the ClamAV scanning process to terminate unexpectedly, leading to a denial-of-service condition on the affected device. There is no information on affected versions or available patches at this time.
Potential Impact
Successful exploitation results in a denial-of-service condition by crashing the ClamAV scanning process. There is no impact on confidentiality or integrity according to the CVSS vector. The vulnerability does not require privileges or user interaction and can be triggered remotely.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, consider restricting or monitoring the submission of zip files for scanning to reduce exposure.
CVE-2026-20337: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') in Cisco Cisco Secure Endpoint
Description
A vulnerability in the zip archive parser of ClamAV allows an unauthenticated remote attacker to cause a denial-of-service (DoS) condition by submitting a specially crafted zip file. The flaw arises from improper boundary checks during zip file scanning, leading to an out-of-bounds write that terminates the scanning process.
CVSS v3.1
Score 7.5high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-20337 is a high-severity vulnerability in ClamAV's zip archive parser caused by improper boundary checks on zip file content during scanning. This results in an out-of-bounds write condition that can be triggered by an unauthenticated remote attacker submitting a maliciously crafted zip file. Exploitation causes the ClamAV scanning process to terminate unexpectedly, leading to a denial-of-service condition on the affected device. There is no information on affected versions or available patches at this time.
Potential Impact
Successful exploitation results in a denial-of-service condition by crashing the ClamAV scanning process. There is no impact on confidentiality or integrity according to the CVSS vector. The vulnerability does not require privileges or user interaction and can be triggered remotely.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, consider restricting or monitoring the submission of zip files for scanning to reduce exposure.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-rhg3-hwfw-hp7p
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-20337"]
- Ecosystems
- []
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
Threat ID: 6a7742a1bf8831d539b08670
Added to database: 08/08/2026, 14:52:17 UTC
Last enriched: 08/08/2026, 15:17:12 UTC
Last updated: 08/09/2026, 03:40:59 UTC
Views: 4
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