Bug 2524161 (CVE-2026-65905)

Summary: CVE-2026-65905 tomcat: Apache Tomcat: Authentication bypass via limited replay attack in DIGEST authenticator
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: csutherl, dsoumis, jclere, jwon, pjindal, plodge, rhel-process-autobot, rmaucher, szappis, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in Apache Tomcat. This vulnerability, an authentication bypass by capture-replay, affects the DIGEST authenticator. A remote attacker can exploit this by making a specially crafted DIGEST authenticated request with a nonceCount at the upper boundary of the replay window. This allows the attacker to replay the request once, potentially bypassing authentication.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-08-25 22:02:25 UTC
Authentication Bypass by Capture-replay vulnerability in Apache Tomcat's DIGEST authenticator. If, before windowSize requests have been made, a client makes a DIGEST 
authenticated request with a nonceCount on the upper boundary of the 
replay window then that request is replayable once only while the 
associated nonceCount remains within the replay window.



 

This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.24, from 10.1.0-M1 through 10.1.57, from 9.0.0.M1 through 9.0.120.



The following versions were EOL at the time the CVE was created but are 
known to be affected: from 8.5.0 through 8.5.100, from 7.0.30 through 7.0.109. Other unsupported versions may also be affected.



Users are recommended to upgrade to version 11.0.25, 10.1.58 or 9.0.121, which fix the issue.