CVE-2026-20039
Description
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.
How to fix
- cisco adaptive_security_appliance_software9.16.4.84, 9.18.4.57, 9.20.3.16, 9.22.2.4, 9.23.1.3 or later
- cisco secure_firewall_threat_defense7.0.9, 7.2.10, 7.4.3, 7.6.1, 7.7.10 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| cisco adaptive_security_appliance_software | 9.12.1 ≤ v < 9.16.4.84, 9.17.1 ≤ v < 9.18.4.57, 9.19.1 ≤ v < 9.20.3.16, 9.22.1.1 ≤ v < 9.22.2.4, 9.23.1 ≤ v < 9.23.1.3 | 9.16.4.84, 9.18.4.57, 9.20.3.16, 9.22.2.4, 9.23.1.3 |
| cisco secure_firewall_threat_defense | 6.4.0 ≤ v < 7.0.9, 7.1.0 ≤ v < 7.2.10, 7.3.0 ≤ v < 7.4.3, 7.6.0 ≤ v < 7.6.1, 7.7.0 ≤ v < 7.7.10 | 7.0.9, 7.2.10, 7.4.3, 7.6.1, 7.7.10 |
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