CVE-2026-76445
Published on October 21, 2026
Multiple Cisco Products Snort 3 Denial of Service Vulnerability
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.
Vulnerability Analysis
CVE-2026-76445 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a small impact on availability.
Weakness Type
What is an Infinite Loop Vulnerability?
The program contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. If the loop can be influenced by an attacker, this weakness could allow attackers to consume excessive resources such as CPU or memory.
CVE-2026-76445 has been classified to as an Infinite Loop vulnerability or weakness.
Affected Versions
Cisco Open Source Snort3:- Version 3.12.2.0 is affected.
- Version 3.1.2.0 is affected.
- Version 3.1.3.0 is affected.
- Version 3.1.4.0 is affected.
- Version 3.1.5.0 is affected.
- Version 3.1.6.0 is affected.
- Version 3.1.7.0 is affected.
- Version 3.1.8.0 is affected.
- Version 3.1.9.0 is affected.
- Version 3.1.10.0 is affected.
- Version 3.1.12.0 is affected.
- Version 3.1.13.0 is affected.
- Version 3.1.14.0 is affected.
- Version 3.1.15.0 is affected.
- Version 3.1.16.0 is affected.
- Version 3.1.17.0 is affected.
- Version 3.1.18.0 is affected.
- Version 3.1.19.0 is affected.
- Version 3.1.20.0 is affected.
- Version 3.1.21.0 is affected.
- Version 3.1.22.0 is affected.
- Version 3.1.23.0 is affected.
- Version 3.1.24.0 is affected.
- Version 3.1.25.0 is affected.
- Version 3.1.27.0 is affected.
- Version 3.1.28.0 is affected.
- Version 3.1.29.0 is affected.
- Version 3.1.30.0 is affected.
- Version 3.1.31.0 is affected.
- Version 3.1.32.0 is affected.
- Version 3.1.36.0 is affected.
- Version 3.1.38.0 is affected.
- Version 3.1.39.0 is affected.
- Version 3.1.40.0 is affected.
- Version 3.1.41.0 is affected.
- Version 3.1.42.0 is affected.
- Version 3.1.43.0 is affected.
- Version 3.1.45.0 is affected.
- Version 3.1.47.0 is affected.
- Version 3.1.48.0 is affected.
- Version 3.1.50.0 is affected.
- Version 3.1.51.0 is affected.
- Version 3.1.52.0 is affected.
- Version 3.1.53.0 is affected.
- Version 3.1.55.0 is affected.
- Version 3.1.56.0 is affected.
- Version 3.1.57.0 is affected.
- Version 3.1.58.0 is affected.
- Version 3.1.59.0 is affected.
- Version 3.1.60.0 is affected.
- Version 3.1.61.0 is affected.
- Version 3.1.62.0 is affected.
- Version 3.1.63.0 is affected.
- Version 3.1.64.0 is affected.
- Version 3.1.65.0 is affected.
- Version 3.1.66.0 is affected.
- Version 3.1.67.0 is affected.
- Version 3.1.69.0 is affected.
- Version 3.1.70.0 is affected.
- Version 3.1.71.0 is affected.
- Version 3.1.72.0 is affected.
- Version 3.1.73.0 is affected.
- Version 3.1.74.0 is affected.
- Version 3.1.75.0 is affected.
- Version 3.1.76.0 is affected.
- Version 3.1.77.0 is affected.
- Version 3.1.78.0 is affected.
- Version 3.1.81.0 is affected.
- Version 3.1.82.0 is affected.
- Version 3.1.83.0 is affected.
- Version 3.1.84.0 is affected.
- Version 3.2.1.0 is affected.
- Version 3.2.2.0 is affected.
- Version 3.3.0.0 is affected.
- Version 3.3.1.0 is affected.
- Version 3.3.2.0 is affected.
- Version 3.3.3.0 is affected.
- Version 3.3.4.0 is affected.
- Version 3.3.5.0 is affected.
- Version 3.3.7.0 is affected.
- Version 3.5.0.0 is affected.
- Version 3.5.1.0 is affected.
- Version 3.8.1.0 is affected.
- Version 3.6.0.0 is affected.
- Version 3.6.2.0 is affected.
- Version 3.9.3.0 is affected.
- Version 3.7.2.0 is affected.
- Version 3.7.0.0 is affected.
- Version 3.9.6.0 is affected.
- Version 3.10.0.0 is affected.
- Version 3.10.2.0 is affected.
- Version 3.7.4.0 is affected.
- Version 3.9.0.0 is affected.
- Version 3.5.2.0 is affected.
- Version 3.12.1.0 is affected.
- Version 3.6.1.0 is affected.
- Version 3.9.2.0 is affected.
- Version 3.6.3.0 is affected.
- Version 3.9.5.0 is affected.
- Version 3.7.1.0 is affected.
- Version 3.9.7.0 is affected.
- Version 3.7.3.0 is affected.
- Version 3.10.1.0 is affected.
- Version 3.9.1.0 is affected.
- Version 3.11.1.0 is affected.
- Version 7.0.0 is affected.
- Version 7.0.0.1 is affected.
- Version 7.0.1 is affected.
- Version 7.0.1.1 is affected.
- Version 7.0.2 is affected.
- Version 7.2.0 is affected.
- Version 7.0.2.1 is affected.
- Version 7.0.3 is affected.
- Version 7.2.0.1 is affected.
- Version 7.0.4 is affected.
- Version 7.2.1 is affected.
- Version 7.0.5 is affected.
- Version 7.3.0 is affected.
- Version 7.2.2 is affected.
- Version 7.2.3 is affected.
- Version 7.3.1 is affected.
- Version 7.2.4 is affected.
- Version 7.0.6 is affected.
- Version 7.2.5 is affected.
- Version 7.2.4.1 is affected.
- Version 7.3.1.1 is affected.
- Version 7.4.0 is affected.
- Version 7.0.6.1 is affected.
- Version 7.2.5.1 is affected.
- Version 7.4.1 is affected.
- Version 7.2.6 is affected.
- Version 7.0.6.2 is affected.
- Version 7.4.1.1 is affected.
- Version 7.2.7 is affected.
- Version 7.2.5.2 is affected.
- Version 7.3.1.2 is affected.
- Version 7.2.8 is affected.
- Version 7.6.0 is affected.
- Version 7.4.2 is affected.
- Version 7.2.8.1 is affected.
- Version 7.0.6.3 is affected.
- Version 7.4.2.1 is affected.
- Version 7.2.9 is affected.
- Version 7.0.7 is affected.
- Version 7.7.0 is affected.
- Version 7.4.2.2 is affected.
- Version 7.2.10 is affected.
- Version 7.6.1 is affected.
- Version 7.4.2.3 is affected.
- Version 7.0.8 is affected.
- Version 7.6.2 is affected.
- Version 7.7.10 is affected.
- Version 7.7.11 is affected.
- Version 7.0.8.1 is affected.
- Version 7.6.2.1 is affected.
- Version 7.7.10.1 is affected.
- Version 7.4.2.4 is affected.
- Version 7.2.10.2 is affected.
- Version 7.4.3 is affected.
- Version 7.6.4 is affected.
- Version 10.0.0 is affected.
- Version 7.4.4 is affected.
- Version 7.0.9 is affected.
- Version 7.2.11 is affected.
- Version 7.4.7 is affected.
- Version 17.12.1a is affected.
- Version 17.12.2 is affected.
- Version 17.12.3 is affected.
- Version 17.12.4 is affected.
- Version 17.12.3a is affected.
- Version 17.15.1a is affected.
- Version 17.12.4a is affected.
- Version 17.15.2c is affected.
- Version 17.12.4b is affected.
- Version 17.15.2a is affected.
- Version 17.12.5 is affected.
- Version 17.12.5a is affected.
- Version 17.15.3a is affected.
- Version 17.15.3 is affected.
- Version 17.12.5b is affected.
- Version 17.12.5c is affected.
- Version 17.15.4 is affected.
- Version 17.18.1 is affected.
- Version 17.18.1a is affected.
- Version 17.12.6 is affected.
- Version 17.15.4c is affected.
- Version 17.12.5d is affected.
- Version 17.18.2 is affected.
- Version 17.15.5 is affected.
- Version 17.15.5a is affected.
- Version 17.12.7 is affected.
- Version 17.12.7a is affected.
- Version 17.12.7b is affected.
- Version 17.18.3a is affected.
- Version 17.12.8 is affected.
- Version 17.15.6 is affected.
- Version 17.18.4 is affected.