CVE-2025-55668: 
Java vulnerability analysis and mitigation

A session fixation vulnerability has been discovered in Apache Tomcat via rewrite valve, identified as CVE-2025-55668. The vulnerability affects multiple versions of Apache Tomcat including 11.0.0-M1 through 11.0.7, 10.1.0-M1 through 10.1.41, and 9.0.0.M1 through 9.0.105, with older EOL versions potentially affected as well. The vulnerability was discovered by Greg K and disclosed on August 13, 2025 (Openwall).

The vulnerability has been classified as having moderate severity and specifically involves session fixation through the rewrite valve component of Apache Tomcat. While detailed technical specifics of the exploitation method are not publicly disclosed in the available sources, the vulnerability relates to session handling mechanisms within the Tomcat server (Apache List).

Session fixation vulnerabilities typically allow attackers to force a user to use a session ID known to the attacker, potentially leading to session hijacking and unauthorized access to user accounts. This could compromise user sessions and potentially lead to unauthorized access to protected resources (Openwall).

Users are strongly recommended to upgrade to the fixed versions: Apache Tomcat 11.0.8, 10.1.42, or 9.0.106, which contain patches for this vulnerability (Openwall).