CVE-2026-66299: Uncontrolled Resource Consumption

July 28, 2026 (updated August 27, 2026)

Uncontrolled Resource Consumption vulnerability in Apache Tomcat’s WebSocket chat example.

This issue affects Apache Tomcat: from 11.0.0-M20 through 11.0.24, from 10.1.24 through 10.1.57, from 9.0.89 through 9.0.120. Users who have followed the security guidance to remove the examples web application are not affected by this issue.

Users are recommended to remove the examples web application or to upgrade to version 11.0.25, 10.1.58 or 9.0.121 (when released), which fix the issue.

References

lists.apache.org/thread/8owczcc1o8qw1rxmg9gvfk4w2jnh4l5k
nvd.nist.gov/vuln/detail/CVE-2026-66299

Code Behaviors & Features

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