CVE-2026-76445

Medium

Description

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.

SeverityMedium
CVSS5.3
Exploit probability—
ProductCisco Open Source Snort3
PublishedOct 21, 2026
First seenOct 21, 2026
Weakness typeCWE-835CWE-835

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
Cisco Cisco Open Source Snort33.12.2.0, 3.1.2.0, 3.1.3.0, 3.1.4.0, 3.1.5.0, 3.1.6.0, 3.1.7.0, 3.1.8.0, 3.1.9.0, 3.1.10.0, 3.1.12.0, 3.1.13.0, 3.1.14.0, 3.1.15.0, 3.1.16.0, 3.1.17.0, 3.1.18.0, 3.1.19.0, 3.1.20.0, 3.1.21.0, 3.1.22.0, 3.1.23.0, 3.1.24.0, 3.1.25.0, 3.1.27.0, 3.1.28.0, 3.1.29.0, 3.1.30.0, 3.1.31.0, 3.1.32.0, 3.1.36.0, 3.1.38.0, 3.1.39.0, 3.1.40.0, 3.1.41.0, 3.1.42.0, 3.1.43.0, 3.1.45.0, 3.1.47.0, 3.1.48.0, 3.1.50.0, 3.1.51.0, 3.1.52.0, 3.1.53.0, 3.1.55.0, 3.1.56.0, 3.1.57.0, 3.1.58.0, 3.1.59.0, 3.1.60.0, 3.1.61.0, 3.1.62.0, 3.1.63.0, 3.1.64.0, 3.1.65.0, 3.1.66.0, 3.1.67.0, 3.1.69.0, 3.1.70.0, 3.1.71.0, 3.1.72.0, 3.1.73.0, 3.1.74.0, 3.1.75.0, 3.1.76.0, 3.1.77.0, 3.1.78.0, 3.1.81.0, 3.1.82.0, 3.1.83.0, 3.1.84.0, 3.2.1.0, 3.2.2.0, 3.3.0.0, 3.3.1.0, 3.3.2.0, 3.3.3.0, 3.3.4.0, 3.3.5.0, 3.3.7.0, 3.5.0.0, 3.5.1.0, 3.8.1.0, 3.6.0.0, 3.6.2.0, 3.9.3.0, 3.7.2.0, 3.7.0.0, 3.9.6.0, 3.10.0.0, 3.10.2.0, 3.7.4.0, 3.9.0.0, 3.5.2.0, 3.12.1.0, 3.6.1.0, 3.9.2.0, 3.6.3.0, 3.9.5.0, 3.7.1.0, 3.9.7.0, 3.7.3.0, 3.10.1.0, 3.9.1.0, 3.11.1.0—
Cisco Cisco Secure Firewall Threat Defense (FTD) Software7.0.0, 7.0.0.1, 7.0.1, 7.0.1.1, 7.0.2, 7.2.0, 7.0.2.1, 7.0.3, 7.2.0.1, 7.0.4, 7.2.1, 7.0.5, 7.3.0, 7.2.2, 7.2.3, 7.3.1, 7.2.4, 7.0.6, 7.2.5, 7.2.4.1, 7.3.1.1, 7.4.0, 7.0.6.1, 7.2.5.1, 7.4.1, 7.2.6, 7.0.6.2, 7.4.1.1, 7.2.7, 7.2.5.2, 7.3.1.2, 7.2.8, 7.6.0, 7.4.2, 7.2.8.1, 7.0.6.3, 7.4.2.1, 7.2.9, 7.0.7, 7.7.0, 7.4.2.2, 7.2.10, 7.6.1, 7.4.2.3, 7.0.8, 7.6.2, 7.7.10, 7.7.11, 7.0.8.1, 7.6.2.1, 7.7.10.1, 7.4.2.4, 7.2.10.2, 7.4.3, 7.6.4, 10.0.0, 7.4.4, 7.0.9, 7.2.11, 7.4.7—
Cisco Cisco UTD SNORT IPS Engine Software17.12.1a, 17.12.2, 17.12.3, 17.12.4, 17.12.3a, 17.15.1a, 17.12.4a, 17.15.2c, 17.12.4b, 17.15.2a, 17.12.5, 17.12.5a, 17.15.3a, 17.15.3, 17.12.5b, 17.12.5c, 17.15.4, 17.18.1, 17.18.1a, 17.12.6, 17.15.4c, 17.12.5d, 17.18.2, 17.15.5, 17.15.5a, 17.12.7, 17.12.7a, 17.12.7b, 17.18.3a, 17.12.8, 17.15.6, 17.18.4—

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CVE-2026-76445 · Cisco Open Source Snort3 · Dark Radar