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.
Apache Tomcat contains a path equivalence vulnerability that allows a remote attacker to execute code, disclose information, or inject malicious content via a partial PUT request. This vulnerability can be chained with CVE‑2026‑34486.
Unchecked Error Condition vulnerability in Apache Tomcat. If Tomcat is configured to use a custom Jakarta Authentication (formerly JASPIC) ServerAuthContext component which may throw an exception during the authentication process without explicitly setting an HTTP status to indicate failure, the authentication may not fail, allowing the user to bypass the authentication process. There are no known Jakarta Authentication components that behave in this way.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.0-M26, from 10.1.0-M1 through 10.1.30, from 9.0.0-M1 through 9.0.95.
The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.0 though 8.5.100. Other EOL versions may also be affected.
Users are recommended to upgrade to version 11.0.0, 10.1.31 or 9.0.96, which fix the issue.