CVE-2026-20179
Multiple Cisco products are affected by a vulnerability in the Snort 3 Generic Routing Encapsulation (GRE) Detection Engine that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart, resulting in an interruption of packet inspection. This vulnerability is due to incomplete error checking when Snort 3 parses GRE packets. An attacker could exploit this vulnerability by sending a crafted GRE packet to a targeted device to be parsed by Snort. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to restart unexpectedly, resulting in a DoS condition.
- Score
- CVSS 3.1 5.8 Medium
- Status
- Awaiting Analysis - psirt@cisco.com
- Published
- 2026-10-21
- Last modified
- 2026-10-22
- Weaknesses
- CWE-128
Affected products
- Cisco Open Source Snort3 (Cisco)
- Cisco Secure Firewall Threat Defense Ftd Software (Cisco)
- Cisco Utd Snort Ips Engine Software (Cisco)
References
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort3-misc-dos-6mB22qAK
