What’s Vulnerable › Vulnerabilities
CVE-2026-24733: Apache Tomcat: Security constraint bypass with HTTP/0.9
- Severity: low (CVSS 3.7 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.6% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-02-17 · updated 2026-06-17
- Weakness: CWE-20
Description
Improper Input Validation vulnerability in Apache Tomcat. Tomcat did not limit HTTP/0.9 requests to the GET method. If a security constraint was configured to allow HEAD requests to a URI but deny GET requests, the user could bypass that constraint on GET requests by sending a (specification invalid) HEAD request using HTTP/0.9. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.14, from 10.1.0-M1 through 10.1.49, from 9.0.0.M1 through 9.0.112. Older, EOL versions are also affected. Users are recommended to upgrade to version 11.0.15 or later, 10.1.50 or later or 9.0.113 or later, which fixes the issue.
Affected products
- Apache Tomcat: from 9.0.1 before 9.0.113; from 10.1.1 before 10.1.50; from 11.0.1 before 11.0.15; 9.0.0-milestone1, 9.0.0-milestone10, 9.0.0-milestone11, 9.0.0-milestone12, 9.0.0-milestone13, 9.0.0-milestone14 (+57) — fixed in 10.1.50, 11.0.15, 9.0.113
How to fix
Upgrade to a fixed version: Apache Tomcat 10.1.50, 11.0.15, 9.0.113. Check the vendor advisory for mitigations.
References
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