cisco-sa-asa-ftd-logging-dos-ZXXNesfN: Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Logging Denial of Service Vulnerability
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. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability.This advisory is available at the following link:https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-ftd-logging-dos-ZXXNesfNThis advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Secure Firewall products, see Cisco Secure Firewall Adaptive Security Appliance Software, Secure Firewall Threat Defense Software, and Secure Firewall Management Center Software Hardening Release: September 2026.
Affected Software
Event History
Frequently Asked Questions
What must an attacker do to trigger the denial of service condition?
An unauthenticated remote attacker can attempt exploitation by sending a flood of TCP SYN packets to an affected device. The issue is tied to improper rate limiting of syslog message 419002.
What is the operational impact of a successful attack?
A successful attack can drive high CPU utilization on the affected device. This can cause performance degradation and result in a denial-of-service condition.
Are updates or mitigations available?
Cisco has released software updates that address the vulnerability. The advisory also states that workarounds are available.