Description
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.
Affected products
apache: tomcat
References2
- lists.apache.org/thread/8owczcc1o8qw1rxmg9gvfk4w2jnh4l5k Mailing ListVendor Advisory
- www.openwall.com/lists/oss-security/2026/07/28/25 Mailing ListThird Party Advisory
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - EPSS — exploit probability
- 1% percentile: 47 · as of 13 November 2026
- CWE
- CWE-400
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