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.
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alma_linux | — | Upgrade tomcat-servlet-4.0-apiUpgrade tomcat-admin-webappsUpgrade tomcat-docs-webappUpgrade tomcat-jsp-2.3-apiUpgrade tomcat-webappsUpgrade tomcat-el-3.0-apiUpgrade tomcatUpgrade tomcat-lib | Oct 11, 2026 | Sep 17, 2026 |
| Amazon Linux Ami 2 | — | Upgrade tomcatUpgrade tomcat-servlet-3.0-apiUpgrade tomcat-el-3.0-apiUpgrade tomcat-jsp-2.3-apiUpgrade tomcat-jsp-2.2-apiUpgrade tomcat-el-2.2-apiUpgrade tomcat-servlet-4.0-apiUpgrade tomcat-docs-webappUpgrade tomcat-admin-webappsUpgrade tomcat-libUpgrade tomcat-javadocUpgrade tomcat-webappsUpgrade tomcat-jsvc | May 20, 2026 | May 20, 2026 |
| Apache Tomcat | — | Upgrade Apache Tomcat to 10.1.50Upgrade Apache Tomcat to the latest available versionUpgrade Apache Tomcat to 9.0.113Upgrade Apache Tomcat to 11.0.15 | Feb 18, 2026 | Feb 17, 2026 |
| Debian | — | Upgrade tomcat10Upgrade tomcat11Upgrade tomcat9 | Feb 19, 2026 | Feb 19, 2026 |
| Redhat_linux | — | Upgrade tomcat9-servlet-4.0-apiUpgrade tomcat-el-3.0-apiUpgrade tomcat-webappsUpgrade jws6-tomcat-servlet-6.0-apiUpgrade tomcat9-libUpgrade jws6-tomcat-libUpgrade tomcat9-webappsUpgrade tomcatUpgrade jws6-tomcat-jsp-3.1-apiUpgrade tomcat9-docs-webappUpgrade tomcat9-admin-webappsNo solution existsUpgrade tomcat-jsp-2.3-apiUpgrade tomcat-docs-webappUpgrade jws6-tomcat-admin-webappsUpgrade tomcat-servlet-4.0-apiUpgrade tomcat9-el-3.0-apiUpgrade jws6-tomcat-docs-webappUpgrade jws6-tomcatUpgrade tomcat9-jsp-2.3-apiUpgrade jws6-tomcat-el-5.0-apiUpgrade jws6-tomcat-webappsUpgrade tomcat9Upgrade tomcat-admin-webappsUpgrade jws6-tomcat-selinuxUpgrade tomcat-libUpgrade jws6-tomcat-javadoc | May 4, 2026 | Feb 17, 2026 |
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