CVE-2026-20249

CVE CVE-2026-20249EUVD EUVD-2026-81118Published 2026-09-16T20:11:43.000ZLast changed 2026-09-18T19:09:05.000ZCVSS 8.6

What the advisory describes

A vulnerability in the certification authentication feature of Internet Key Exchange version 2 (IKEv2) for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly. This vulnerability is due to a logic error during the certificate authentication phase of the IKEv2 connection setup. An attacker could exploit this vulnerability by attempting to establish an IKEv2 VPN connection with a crafted certificate. A successful exploit could allow the attacker to cause the IKEv2 process to crash, causing a denial of service (DoS) condition.

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

Cisco — Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.19.1.24; 9.18.4.52; 9.22.1.2; 9.20.2; 9.22.2.13; 9.18.2.7; 9.16.4.18; 9.20.3.13; 9.24.1.5; 9.16.3.19; 9.20.3.20; 9.20.1.5; 9.16.4.27; 9.18.4.67; 9.20.2.22; 9.16.2.14; 9.20.4.7; 9.24.1.9; 9.20.4.14; 9.18.4.53; 9.16.4.71; 9.20.4.30; 9.18.4.82; 9.16.4.38; 9.20.4.22; 9.16.1.28; 9.19.1.38; 9.16.4.14; 9.19.1.5; 9.22.2.32; 9.19.1; 9.16.4.67; 9.18.4.47; 9.22.2.9; 9.18.4.34; 9.20.3.7; 9.22.2.20; 9.19.1.12; 9.20.4.10; 9.16.4.70; 9.16.4.92; 9.20.2.21; 9.16.4.57; 9.23.1; 9.23.1.195; 9.23.1.26; 9.18.4; 9.18.3.56; 9.16.2.13; 9.18.1.3; 9.22.2.4; 9.18.2.8; 9.18.4.8; 9.16.4.39; 9.20.4; 9.16.3.14; 9.16.1; 9.16.3; 9.19.1.9; 9.16.2.7; 9.23.1.32; 9.18.4.135; 9.16.4.84; 9.19.1.27; 9.18.3.39; 9.23.1.19; 9.22.2.14; 9.20.3.10; 9.18.4.76; 9.18.3.55; 9.20.4.19; 9.20.3; 9.18.4.57; 9.22.1.6; 9.20.2.10; 9.18.2.5; 9.19.1.28; 9.16.4.85; 9.16.2.3; 9.19.1.37; 9.16.4.9; 9.22.3; 9.16.2; 9.16.4.48; 9.18.2; 9.16.3.23; 9.18.4.66; 9.20.3.4; 9.16.4.42; 9.24.1; 9.18.4.68; 9.20.3.9; 9.16.4.61; 9.18.4.22; 9.23.1.7; 9.20.3.16; 9.20.1; 9.18.4.50; 9.24.1.155; 9.18.3.53; 9.16.2.11; 9.18.4.5; 9.23.1.3; 9.18.4.24; 9.19.1.31; 9.18.4.71; 9.22.1.3; 9.16.4.76; 9.16.3.3; 9.16.4.82; 9.23.1.22; 9.18.3; 9.18.1; 9.19.1.18; 9.18.4.29; 9.20.4.28; 9.19.1.22; 9.16.4; 9.22.2; 9.22.1.1; 9.16.4.62; 9.18.3.46; 9.16.4.89; 9.19.1.42; 9.23.1.13; 9.16.4.19; 9.16.4.55; 9.16.3.15; 9.18.4.40
Cisco — Cisco Secure Firewall Threat Defense (FTD) Software 7.4.2.2; 7.2.7; 7.0.0.1; 7.2.6; 7.0.6.3; 7.2.5.2; 7.0.2.1; 7.7.10.1; 7.0.6; 7.2.4; 7.2.10; 7.0.9; 7.3.0; 7.0.3; 7.3.1; 7.4.3; 7.4.1.1; 7.0.8.1; 7.7.10; 7.4.0; 7.2.3; 7.2.8.1; 7.2.9; 7.2.11; 7.2.2; 7.2.5; 7.2.8; 7.6.0; 7.6.1; 7.0.1; 7.7.11; 7.0.6.2; 7.4.2.3; 7.0.5; 7.6.4; 7.3.1.1; 7.4.2.4; 7.0.7; 10.0.0; 7.0.0; 7.7.0; 7.4.2; 7.2.5.1; 7.2.0.1; 7.6.2; 7.0.1.1; 7.4.4; 7.4.2.1; 7.2.4.1; 7.2.0; 7.6.2.1; 7.2.10.2; 7.4.1; 7.0.4; 7.0.8; 7.0.6.1; 7.2.1; 7.4.7; 7.0.2; 7.3.1.2

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.

Cisco — Secure Firewall Adaptive Security Appliance (ASA) Software
Cisco — Secure Firewall Threat Defense (FTD) Software

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