Improper Input Validation vulnerability.
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.
The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.0 through 8.5.100. Older EOL versions are not affected. Tomcat did not validate that the host name provided via the SNI extension was the same as the host name provided in the HTTP host header field. If Tomcat was configured with more than one virtual host and the TLS configuration for one of those hosts did not require client certificate authentication but another one did, it was possible for a client to bypass the client certificate authentication by sending different host names in the SNI extension and the HTTP host header field.
The vulnerability only applies if client certificate authentication is only enforced at the Connector. It does not apply if client certificate authentication is enforced at the web application.
Users are recommended to upgrade to version 11.0.15 or later, 10.1.50 or later or 9.0.113 or later, which fix the issue.
CVSS Details
- CVSS 3.1 Base Score: 9.1
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alma_linux | — | Upgrade tomcat-admin-webappsUpgrade tomcat-jsp-2.3-apiUpgrade tomcat-servlet-4.0-apiUpgrade tomcat-el-3.0-apiUpgrade tomcat-docs-webappUpgrade tomcat-libUpgrade tomcat-webappsUpgrade tomcat | Oct 11, 2026 | Sep 17, 2026 |
| Amazon Linux Ami 2 | — | Upgrade tomcat-jsvcUpgrade tomcat-servlet-4.0-apiUpgrade tomcat-jsp-2.3-apiUpgrade tomcat-el-3.0-apiUpgrade tomcat-admin-webappsUpgrade tomcatUpgrade tomcat-docs-webappUpgrade tomcat-webappsUpgrade tomcat-lib | 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 11.0.15Upgrade Apache Tomcat to 9.0.113 | Feb 18, 2026 | Feb 17, 2026 |
| Debian | — | Upgrade tomcat11Upgrade tomcat9Upgrade tomcat10 | Feb 19, 2026 | Feb 19, 2026 |
| Redhat_linux | — | Upgrade jws6-tomcat-docs-webappUpgrade tomcat-jsp-2.3-apiUpgrade tomcat-el-3.0-apiUpgrade tomcatUpgrade jws6-tomcat-libUpgrade jws6-tomcat-admin-webappsUpgrade jws6-tomcat-webappsUpgrade jws6-tomcat-jsp-3.1-apiUpgrade tomcat-admin-webappsUpgrade jws6-tomcatUpgrade tomcat-webappsUpgrade tomcat9-admin-webappsUpgrade tomcat9-webappsUpgrade tomcat9-el-3.0-apiUpgrade tomcat-docs-webappUpgrade tomcat-servlet-4.0-apiUpgrade jws6-tomcat-servlet-6.0-apiUpgrade tomcat9-docs-webappUpgrade tomcat9-libUpgrade jws6-tomcat-el-5.0-apiUpgrade tomcat9-jsp-2.3-apiUpgrade tomcat-libUpgrade jws6-tomcat-selinuxUpgrade jws6-tomcat-javadocUpgrade tomcat9Upgrade tomcat9-servlet-4.0-apiNo solution exists | May 4, 2026 | Feb 17, 2026 |
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