CVE-2026-55955: Apache Tomcat

Medium severity, CVSS 6.5. EPSS: 0.4% chance of exploitation in the next 30 days.

Improper Authentication vulnerability in Apache Tomcat allowed a replay attack against the EncryptionInterceptor in the cluster component. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.13 through 9.0.18, from 8.5.38 through 8.5.100, from 7.0.100 through 7.0.109. Users are recommended to upgrade to version 11.0.23, 10.1.56, 9.0.119, which fixes the issue.

Affected products

• Apache Tomcat: before 9.0.119 (fixed in 9.0.119); from 10.1.0, before 10.1.56 (fixed in 10.1.56); from 11.0.0, before 11.0.23 (fixed in 11.0.23)

Published 2026-06-29. Last modified 2026-07-10.