CVE-2026-66299
Uncontrolled Resource Consumption vulnerability in Apache Tomcat's WebSocket chat example.
Does this matter?
Lower severity and a low EPSS score (0.53%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 3.1
- 5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- EPSS
- 0.53% probability · 43th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-400
- Affected
- apache/tomcat
- Source
- security@apache.org
References
- https://lists.apache.org/thread/8owczcc1o8qw1rxmg9gvfk4w2jnh4l5kMailing List, Vendor Advisory
- http://www.openwall.com/lists/oss-security/2026/07/28/25Mailing List, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.