Vulnerability in Cisco Open Source Snort3
CVE-2026-76445
Multiple Cisco products are affected by a vulnerability in the Snort 3 Detection Engine that could allow an unauthenticated, remote attacker to cause the detection engine to unexpectedly restart, resulting in a denial of service (DoS) condition. The vulnerability is due to a flaw in logic handling when General Packet Radio Service (GPRS) Tunneling Protocol (GTP) extension headers are processed within the codec. An attacker could exploit this vulnerability by sending a crafted, fragmented UDP datagram that contains these headers to the Snort 3 Detection Engine of an affected device. A successful exploit could allow the attacker to cause the detection engine to enter an infinite loop, resulting in a DoS condition.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Cisco Open Source Snort3 — versions 3.1.10.0, 3.1.12.0, 3.1.13.0
- Cisco Secure Firewall Threat Defense (Ftd) Software — versions 10.0.0, 7.0.0, 7.0.0.1
- Cisco Utd Snort Ips Engine Software — versions 17.12.1a, 17.12.2, 17.12.3
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-76445?
- CVE-2026-76445 is a medium-severity vulnerability in Cisco Open Source Snort3, classified under Loop with Unreachable Exit Condition (Infinite Loop). CVSS score: 5.3/10. Published 2026-10-21.
- How severe is CVE-2026-76445?
- Medium severity. CVSS v3 base score is 5.3 out of 10.