CVE-2026-55955
Received Received - Intake

Improper Authentication in Apache Tomcat Replay Attack

Publication date: 2026-06-29

Last updated on: 2026-06-29

Assigner: Apache Software Foundation

Description
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.

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Meta Information

Published
2026-06-29
Last Modified
2026-06-29
Generated
2026-06-30
AI Q&A
2026-06-30
EPSS Evaluated
N/A
NVD
CVE-2026-55955

Affected Vendors & Products

Showing 5 associated CPEs
Vendor Product Version / Range
apache tomcat From 11.0.0-M1 (inc) to 11.0.22 (inc)
apache tomcat From 10.1.0-M1 (inc) to 10.1.55 (inc)
apache tomcat From 9.0.13 (inc) to 9.0.18 (inc)
apache tomcat From 8.5.38 (inc) to 8.5.100 (inc)
apache tomcat From 7.0.100 (inc) to 7.0.109 (inc)

Helpful Resources

Exploitability

CWE
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KEV
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CWE ID Description
CWE-287 When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

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Executive Summary

This vulnerability is an Improper Authentication issue in Apache Tomcat that allows a replay attack against the EncryptionInterceptor component used in clustering.

A replay attack means that an attacker can capture and reuse valid authentication data to gain unauthorized access or perform actions without proper authentication.

Impact Analysis

This vulnerability can allow an attacker to bypass authentication mechanisms in Apache Tomcat's cluster component by replaying intercepted authentication data.

As a result, unauthorized users might gain access to restricted cluster communications or perform actions that should require proper authentication.

Mitigation Strategies

Users are recommended to upgrade Apache Tomcat to version 11.0.23, 10.1.56, or 9.0.119, which fixes the Improper Authentication vulnerability allowing replay attacks against the EncryptionInterceptor in the cluster component.

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