Inconsistent interpretation of HTTP requests in Cisco Firewall Threat Defense (FTD) and Cisco Adaptive Security Appliance (ASA) - CVE-2026-20069
Published: March 9, 2026
Vulnerability identifier: #VU123651
CSH Severity: Medium
CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-20069
CWE-ID: CWE-444
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform HTTP request smuggling attacks.
The vulnerability exists due to improper validation of HTTP requests. A remote attacker can send a specially crafted HTTP request to the device with enabled VPN features and smuggle arbitrary HTTP headers.
Successful exploitation of vulnerability may allow an attacker to poison HTTP cache and perform phishing attacks.
Affected software
Cisco Firewall Threat Defense (FTD)
Cisco Adaptive Security Appliance (ASA)
Cisco Adaptive Security Appliance (ASA)
How to mitigate CVE-2026-20069
Install updates from vendor's website.
Cisco Firewall Threat Defense (FTD) - addressed in versions 7.0.9, 7.2.11, 7.4.3, 7.6.4, 7.7.11
Cisco Adaptive Security Appliance (ASA) - addressed in versions 9.16.4.85, 9.18.4.66, 9.20.4.7, 9.22.2.13, 9.23.1.13, 9.24.1
Cisco Adaptive Security Appliance (ASA) - addressed in versions 9.16.4.85, 9.18.4.66, 9.20.4.7, 9.22.2.13, 9.23.1.13, 9.24.1