CVE-2026-76445

Multiple Cisco Products Snort 3 Denial of Service Vulnerability

MEDIUM

5.3

CVSS Score

Published: October 21, 2026 at 04:14 PM UTC

Updated: October 22, 2026 at 07:11 PM UTC

3 products affected across 1 vendorSecure Firewall Threat DefenseUnified Threat Defense Snort Intrusion Prevention System EngineCisco Open Source Snort3

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Severity

MEDIUM5.3

Exploit prediction

EPSS 0.5%

SSVC

No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Cisco Open Source Snort3 · Cisco

90%

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