CVE-2026-66299
Low
No strong exploitation signal.
CVSS base
5.3
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS — probability of exploitation (30 days)
0.5%
43.9th percentile
CISA KEV
Not listed
Weakness / dates
CWE-400
Published 2026-07-28 · modified 2026-08-27
CVSS breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
| Attack Vector | N | Network |
| Attack Complexity | L | Low |
| Privileges Required | N | None |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | N | None |
| Integrity | N | None |
| Availability | L | Low |
Timeline
- 2026-07-28 — Published (NVD)
- 2026-08-27 — Last modified (NVD)
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.