23 Oct 2026 15:48:27 UTC
Cisco Secure Firewall Adaptive Security Appliance Software and Secure Firewall Threat Defense Software Logging Denial of Service
cve-program · CVE-2026-20154 · Published
CVE-2026-20154
Cisco Secure Firewall Adaptive Security Appliance (ASA) Software · denial of service
CVSS 3.1 8.6 HIGHCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-20154
PublishedA 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.
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