DoS via Snort3 Engine Restart in Cisco Devices
CVE-2026-20065 Published on March 4, 2026

Multiple Cisco Products Snort 3 TBD 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 Snort 3 Detection Engine to restart, resulting in an interruption of packet inspection. This vulnerability is due to an error in the binder module initialization logic of the Snort Detection Engine. An attacker could exploit this vulnerability by sending certain packets through an established connection that is parsed by Snort 3. A successful exploit could allow the attacker to cause a DoS condition when the Snort 3 Detection Engine restarts unexpectedly.

NVD

Vulnerability Analysis

CVE-2026-20065 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.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
NONE
User Interaction:
NONE
Scope:
CHANGED
Confidentiality Impact:
NONE
Integrity Impact:
NONE
Availability Impact:
LOW

Weakness Type

Improper Locking

The software does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors.


Affected Versions

Cisco Secure Firewall Threat Defense (FTD) Software: Cisco UTD SNORT IPS Engine Software:

Exploit Probability

EPSS
0.09%
Percentile
24.53%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.