CVE-2026-66299 (GCVE-0-2026-66299)

Vulnerability from cvelistv5 – Published: 2026-07-28 14:29 – Updated: 2026-07-28 17:40
VLAI
Title
Apache Tomcat: DoS via WebSocket chat example
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
References
Impacted products
Vendor Product Version
Apache Software Foundation Apache Tomcat Affected: 11.0.0-M20 , ≤ 11.0.24 (semver)
Affected: 10.1.24 , ≤ 10.1.57 (semver)
Affected: 9.0.89 , ≤ 9.0.120 (semver)
Unaffected: 0 , ≤ 8.5.100 (semver)
Create a notification for this product.
Credits
4ra1n, pyn3rd and unam4
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.