CVE-2019-17563
HighCVSS 7.5Exploitation Probability (EPSS)
Very high risk96th percentile - higher than 96% of all known CVEs
Summary
In Apache Tomcat versions 9.0.0.M1 to 9.0.29, 8.5.0 to 8.5.49, and 7.0.0 to 7.0.98, when using FORM authentication, there is a narrow window where an attacker could perform a session fixation attack. The window was considered too narrow for practical exploitation, but it has been treated as a security vulnerability out of caution.
Risk Assessment
Potential session hijacking, which could lead to unauthorized access to user accounts.
Recommendation
Update Apache Tomcat to a version that includes a fix for this vulnerability.
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Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS