5.3mediumMedium
CVE-2026-66299
Apache Tomcat
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.
Exploitation status
- A vendor advisory or patch reference has been published.
What the metrics mean
- It is reachable over a network, without needing local access.
- For an attacker who can reach it, no special conditions are needed to exploit it.
- To exploit it, no account is needed.
- Beyond that, no action by a user is required.
Scoring
- CVSS
- 5.3 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L- Weakness
- CWE-400
- Assigned by
- security@apache.org
Dates
- Published
- 2026-07-28
- Last modified
- 2026-08-27
- Sources
- NVD
Affected products
- Apache Tomcat9.0.89 - 9.0.121, 10.1.24 - 10.1.58, 11.0.1 - 11.0.25, 11.0.0
As listed in the NVD configuration data. Not a statement about your estate.