CVE-2026-20290

Cisco Secure Firewall Threat Defense Software Snort 2 SSL/TLS Denial of Service Vulnerability

Published: Sep 16, 2026Updated: Sep 18, 2026 Sources: CVE List NVDCWE-805

5.8MEDIUM

Description

A vulnerability in SSL/TLS certificate parsing in the Snort 2 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the Snort 2 Detection Engine to restart. This vulnerability is due to incomplete validation of the SSL certificate. An attacker could exploit this vulnerability by sending a crafted SSL connection setup request to be parsed by Snort 2. A successful exploit could allow the attacker to cause the Snort 2 Detection Engine to restart unexpectedly, resulting in a denial of service (DoS) condition.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:CScope

Changed

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:LAvailability

Low

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Weaknesses

CWE-805

Affected Products

Cisco

commercial·USaka cisco systems inc., cisco systems

Cisco Secure Firewall Threat Defense (FTD) Software

Networking Infrastructure

Exploitability

0 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

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References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-snort2-ssldos-Mw7WYX9c

sec.cloudapps.cisco.com

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