CVE-2019-17563: High severity IBM Data Risk Manager vulnerability

It was found that tomcat's FORM authentication allowed a very small period in which an attacker could possibly force a victim to use a valid user session, or Session Fixation. While practical exploit of this issue is deemed highly improbable, an abundance of caution merits it be considered a flaw. The highest threat from this vulnerability is to system availability, but also threatens data confidentiality and integrity.

When using FORM authentication there was a narrow window where an attacker could perform a session fixation attack. The window was considered too narrow for an exploit to be practical but, erring on the side of caution, this issue has been treated as a security vulnerability.

Reference: https://tomcat.apache.org/security-7.html https://tomcat.apache.org/security-8.html http://tomcat.apache.org/security-9.html

Upstream commits: https://github.com/apache/tomcat/commit/ab72a10 https://github.com/apache/tomcat/commit/e19a202 https://github.com/apache/tomcat/commit/1ecba14

— Red Hat

When using FORM authentication with Apache Tomcat 9.0.0.M1 to 9.0.29, 8.5.0 to 8.5.49 and 7.0.0 to 7.0.98 there was a narrow window where an attacker could perform a session fixation attack. The window was considered too narrow for an exploit to be practical but, erring on the side of caution, this issue has been treated as a security vulnerability.