CVE-2026-76183

Apache Tomcat: Bypass of security constraints for WebSocket endpoints

Published: Sep 23, 2026Updated: Sep 23, 2026 Sources: CVE List NVDCWE-289

9.8CRITICAL

Description

Authentication Bypass by Alternate Name vulnerability in Apache Tomcat allowed the security constraints for any WebSocket endpoint to be bypassed. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.0.M1 through 9.0.121. The following versions were EOS at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.43 through 7.0.109. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:HAvailability

High

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Weaknesses

CWE-289

Affected Products

Apache Software Foundation

oss-project·USaka apache foundation

Apache TomcatOn-premWeb App

Networking Infrastructure / load-balancer-proxy

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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References

https://lists.apache.org/thread/45mxk8nj2q8pkhct6lfxkvtm2jpywrsp

lists.apache.org

http://www.openwall.com/lists/oss-security/2026/09/23/21

openwall.com

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