cisco-sa-ftd-dnd-dos-bpEcg7B7MediumCVSS 6.8

Cisco Secure Firewall Threat Defense Software SSL Decryption Policy Denial of Service Vulnerability

Published
March 4, 2026
Last Modified
March 4, 2026

🔗 CVE IDs covered (1)

CVE-2026-20050 →

📋 Description

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.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is part of the March 2026 release of the Cisco Secure Firewall ASA, Secure FMC, and Secure FTD Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: March 2026 Semiannual Cisco Secure Firewall ASA, Secure FMC, and Secure FTD Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-75736"].

CVE-2026-20050 — Cisco Secure Firewall Threat Defense Decryption Policy Denial of Service Vulnerability (CVSS 3.1 6.8, CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H)

🎯 Affected products51

  • Cisco 3000 Series Industrial Security Appliances (ISA)
  • Cisco Firepower 1000 Series
  • Cisco Firepower 2100 Series
  • Cisco Firepower 4100 Series
  • Cisco Firepower 9000 Series
  • Cisco Secure Firewall 1200 Series
  • Cisco Secure Firewall 3100 Series
  • Cisco Secure Firewall 4200 Series
  • Cisco Secure Firewall Threat Defense (FTD) Software
  • Cisco Secure Firewall Threat Defense Virtual
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.1.0
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.1.0.1
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.1.0.2
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.1.0.3
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.0
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.0.1
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.1
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.10
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.10.2
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.2
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.3
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.4
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.4.1
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.5
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.5.1
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.5.2
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.6
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.7
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.8
  • Cisco Secure Firewall Threat Defense (FTD) Software 7.2.8.1
  • +21 more not shown

✅ Remediation

Cisco has released software updates that address this vulnerability. https://software.cisco.com Workarounds: There are no workarounds that address this vulnerability.

🔗 References (7)