CVE-2026-66299
5.3 · MEDIUMOverview
CVE-2026-66299 is a medium-severity vulnerability affecting apache tomcat. It was published on July 28, 2026 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from apache. Update tomcat to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| apache | tomcat | >= 9.0.89, < 9.0.121 | Affected |
Frequently Asked Questions
What is CVE-2026-66299?
CVE-2026-66299 is a medium-severity vulnerability affecting apache tomcat. It was published on July 28, 2026 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
How severe is CVE-2026-66299?
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-66299?
Check the references section for vendor advisories and patches from apache. Update tomcat to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-66299?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-66299 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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