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CVE-2026-20039

Cisco Adaptive Security Appliance and Firepower Threat Defense Software SSL VPN Authentication Denial of Service Vulnerability

Published
Last modified
published
Not listed in CISA KEV
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: yes
  • Technical impact: partial

Summary

A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and 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 ineffective memory management of the VPN web server. An attacker could exploit this vulnerability by sending a large number of crafted HTTP requests to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: yes · Technical impact: partial

  3. Record last updated

Affected versions

  • Cisco Cisco Secure Firewall Adaptive Security Appliance (ASA) Software

    9.12.3, 9.12.1, 9.12.2, 9.12.4, 9.12.3.2, 9.12.3.7, 9.12.2.5, 9.12.3.12, 9.12.1.3, 9.12.2.4, 9.12.1.2, 9.12.2.9, 9.12.3.9, 9.12.2.1, 9.12.4.2, 9.12.4.4, 9.12.4.7, 9.12.4.8, 9.12.4.10, 9.12.4.13, 9.12.4.18, 9.12.4.24, 9.16.1, 9.12.4.26, 9.16.1.28, 9.12.4.29, 9.16.2, 9.12.4.30, 9.16.2.3, 9.12.4.35, and 112 more

  • Cisco Cisco Secure Firewall Threat Defense (FTD) Software

    6.4.0.1, 6.4.0.2, 6.4.0.5, 6.4.0, 6.4.0.3, 6.4.0.4, 6.4.0.6, 6.4.0.7, 6.4.0.8, 6.4.0.9, 6.4.0.10, 6.4.0.11, 6.4.0.12, 7.0.0, 7.0.0.1, 7.0.1, 7.1.0, 6.4.0.13, 7.0.1.1, 6.4.0.14, 7.1.0.1, 7.0.2, 6.4.0.15, 7.2.0, 7.0.2.1, 7.0.3, 7.1.0.2, 7.2.0.1, 7.0.4, 7.2.1, and 38 more

References 1

sec.cloudapps.cisco.com