CVE-2026-20154

CVE CVE-2026-20154EUVD EUVD-2026-81128Published 2026-09-16T20:13:40.000ZLast changed 2026-09-18T19:09:05.000ZCVSS 8.6

What the advisory describes

A vulnerability in the system rate-limiting process for syslog message 419002 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 high CPU utilization on an affected device, resulting in a denial of service (DoS) condition. This vulnerability is due to improper rate limiting for syslog message 419002. An attacker could exploit this vulnerability by sending a flood of TCP synchronization (SYN) packets to an affected device. A successful exploit could allow the attacker to cause high CPU utilization, resulting in performance degradation. 

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

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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