CVE-2026-29146: Apache Tomcat: EncryptInterceptor vulnerable to padding oracle attack by default

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 8.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-04-09 · updated 2026-10-26
Weakness: CWE-209

Description

Padding Oracle vulnerability in Apache Tomcat's EncryptInterceptor with default configuration. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.18, from 10.0.0-M1 through 10.1.52, from 9.0.13 through 9..115, from 8.5.38 through 8.5.100, from 7.0.100 through 7.0.109. Users are recommended to upgrade to version 11.0.19, 10.1.53 and 9.0.116, which fixes the issue.

Affected products

Apache Tomcat: from 7.0.100 through 7.0.109; from 8.5.38 through 8.5.100; from 9.0.13 before 9.0.116; from 10.0.0 before 10.1.53; from 11.0.0 before 11.0.20 — fixed in 9.0.116, 10.1.53, 11.0.20

How to fix

Upgrade to a fixed version: Apache Tomcat 9.0.116, 10.1.53, 11.0.20. Check the vendor advisory for mitigations.

References

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