CVE-2026-20154 — Cisco Secure Firewall Adaptive Security Appliance Software and Secure Firewall Threat Defense Software Logging Denial of Service
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 Threa…
Published: 2026-09-16 · CVSS: 8.6 · CVSS 3.1
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: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7