CVE-2026-20050 MEDIUM

CVE-2026-20050: Cisco Secure Firewall Threat Defense Decryption Policy Denial of Service Vulnerability

Vendor Cisco
Product Cisco Secure Firewall Threat Defense (FTD) Software
Weakness CWE-404
Published March 4, 2026
Last update March 4, 2026

CVSS base score

6.8/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H

What the vulnerability does

01Description

A vulnerability in the Do Not Decrypt exclusion feature of the SSL decryption feature of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper memory management during the inspection of TLS 1.2 encrypted traffic. An attacker could exploit this vulnerability by sending crafted TLS 1.2 encrypted traffic through an affected device. A successful exploit could allow the attacker to cause a reload of an affected device. Note: This vulnerability only affects traffic that is encrypted by TLS 1.2. Other versions of TLS are not affected.

Key dates

02Disclosure timeline

March 4, 2026 CVE published
March 4, 2026 Record updated