CVE-2026-65905: Apache Tomcat: Limited replay attack possible with DIGEST authentication
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.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Apache Tomcatto a version that resolves this vulnerability.Fixed in 11.0.25 - Upgrade
Upgrade
Apache Tomcatto a version that resolves this vulnerability.Fixed in 10.1.58 - Upgrade
Upgrade
Apache Tomcatto a version that resolves this vulnerability.Fixed in 9.0.121 - Upgrade
Upgrade
Apache Tomcatto a version that resolves this vulnerability.Fixed in 8.5.100 - Upgrade
Upgrade
Apache Tomcatto a version that resolves this vulnerability.Fixed in 7.0.109
Event History
Frequently Asked Questions
Which deployments are exposed to this issue?
Deployments using Apache Tomcat's DIGEST authenticator are exposed if they run versions 11.0.0-M1 through 11.0.24, 10.1.0-M1 through 10.1.57, or 9.0.0.M1 through 9.0.120. Known affected end-of-life releases include 8.5.0 through 8.5.100 and 7.0.30 through 7.0.109; other unsupported versions may also be affected.
What does an attacker need to exploit the replay condition?
The attacker needs to capture a DIGEST-authenticated request made before windowSize requests have occurred, where the client used a nonceCount at the upper boundary of the replay window. That captured request can then be replayed once while its associated nonceCount remains within the replay window.
What versions remediate the issue?
Upgrade to Apache Tomcat 11.0.25, 10.1.58, or 9.0.121. These versions fix the issue.