CVE-2026-20243
Last modified
CVE-2026-20243 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. A vulnerability in the ALZ file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected device. This vulnerability is due to improper boundary checks for content in ALZ files during scanning, which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by submitting a crafted file that contains ALZ content to be scanned by ClamAV on an affected device. EPSS estimates a 0.39% chance of exploitation in the next 30 days.
Description
A vulnerability in the ALZ file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected device. This vulnerability is due to improper boundary checks for content in ALZ files during scanning, which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by submitting a crafted file that contains ALZ content to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting in a DoS condition on the affected software.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Secure Endpoint | < 1.27.2 |
| Cisco | Secure Endpoint | < 1.29.0 |
| Cisco | Secure Endpoint | < 8.6.2 |
| Clamav | Clamav | >= 1.4.0, < 1.4.5 |
| Clamav | Clamav | >= 1.5.0, < 1.5.3 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
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