CVE-2026-73180: Apache Tomcat: Authenticated WebSocket session survives end of HTTP session
Insufficient Session Expiration vulnerability in Apache Tomcat meant that if the session ID for an authenticated HTTP session was changed after a WebSocket connection had been established under that authenticated HTTP session, the WebSokcet session would not be closed as required by the Jakarta WebSocket specification when the HTTP session ended.
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 7.0.43 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
Event History
Frequently Asked Questions
What conditions are required for this issue to occur?
An authenticated HTTP session must have already established a WebSocket connection, and the HTTP session ID must then be changed. When that HTTP session ends, the associated WebSocket session may remain open instead of being closed.
Which Tomcat deployments are affected?
Affected supported release ranges are 11.0.0-M1 through 11.0.24, 10.1.0-M1 through 10.1.57, and 9.0.0.M1 through 9.0.120. Known affected end-of-life ranges are 8.5.0 through 8.5.100 and 7.0.43 through 7.0.109; other unsupported versions may also be affected.
What versions fix the issue?
Upgrade to Apache Tomcat 11.0.25, 10.1.58, or 9.0.121, as applicable to the maintained release line.