CVE-2026-78383 is a high severity vulnerability in Apache Tomcat involving allocation of resources without limits or throttling. It allows an unauthenticated AJP request to pin an AJP processing thread, causing denial of service. Affected versions include Apache Tomcat from 11.0.0-M1 through 11.0.25, 10.1.0-M1 through 10.1.59, 9.0.0.M1 through 9.0.121, and some older EOL versions. Upgrading to versions 11.0.26, 10.1.60, or 9.0.122 mitigates the issue.
CVE-2026-77791 is an Uncontrolled Resource Consumption vulnerability in Apache Tomcat that allows a denial-of-service (DoS) attack during the sending of WebSocket close messages. This affects multiple Apache Tomcat versions, including 11.0.0-M5 through 11.0.25, 10.1.8 through 10.1.59, 9.0.74 through 9.0.121, and some end-of-life versions 8.5.88 through 8.5.100. Users are advised to upgrade to fixed versions 11.0.26, 10.1.60, or 9.0.122 to mitigate the issue. The vulnerability has a CVSS score of 7.5, indicating high severity.
CVE-2026-73581 is an improper check for certificate revocation vulnerability in Apache Tomcat's TLS implementations using OpenSSL and OpenSSL-FFM. The issue causes the system to ignore Certificate Revocation Lists (CRLs) when certificates use a keystore, potentially allowing revoked certificates to be accepted. This affects multiple Apache Tomcat versions from 8.5.0 through 11.0.25. Fixed versions include 11.0.26, 10.1.59, 9.0.122, and 8.5.101.
This security update for Apache Tomcat addresses multiple vulnerabilities including security constraint bypasses, time-of-check to time-of-use (TOCTOU) issues, incomplete fixes in HTTP/2 strict SNI validation, replay attacks in DIGEST authentication, access control bypasses in RewriteValve, memory exhaustion via WebSocket example, role constraint bypasses, and denial of service via HTTP/2 backlog tracking. The update also includes fixes for authentication and session management issues. The vulnerabilities are fixed in Tomcat version 9.0.121.
Improper Handling of URL Encoding (Hex Encoding) vulnerability in Apache Tomcat's rewrite valve allowed security constraint bypass for some configurations.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.23, from 10.1.0-M1 through 10.1.56, from 9.0.0.M1 through 9.0.119, from 8.5.0 through 8.5.100. Other versions that have reached end of support may also be affected.
Users are recommended to upgrade to version 11.0.24, 10.1.57 or 9.0.120, which fix the issue.
Insufficient Technical Documentation vulnerability in Apache Tomcat since the requirements to securely configure the EncryptInterceptor were not clearly documented.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.23, from 10.1.0-M1 through 10.1.56, from 9.0.13 through 9.0.119, from 8.5.38 through 8.5.100, from 7.0.100 through 7.0.109. Other versions that have reached end of support may also be affected.
Users are recommended to upgrade to version 11.0.24, 10.1.57 or 9.0.120 which fix the issue.
Missing Critical Step in Authentication vulnerability in Apache Tomcat when the JNDIRealm was configured to authenticate binds using GSSAPI allowed attackers to authenticate without provided the correct password.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.4, from 10.1.0-M1 through 10.1.36, from 9.0.0.M1 through 9.0.100, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109.
Users are recommended to upgrade to version 11.0.5, 10.1.37 or 9.0.101, which fixes the issue.
Improper Authorization vulnerability in Apache Tomcat leads to security constraints specified for the default servlet ignoring any method or method omission configured as part of the constraint.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.0.M1 through 9.0.118, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other versions that have reached end of support may also be affected.
Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119, which fix the issue.
Improper Authentication vulnerability in Apache Tomcat allowed a replay attack against the EncryptionInterceptor in the cluster component.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.13 through 9.0.18, from 8.5.38 through 8.5.100, from 7.0.100 through 7.0.109.
Users are recommended to upgrade to version 11.0.23, 10.1.56, 9.0.119, which fixes the issue.
Always-Incorrect Control Flow Implementation vulnerability in Apache Tomcat meant that special roles and empty authorisation constraints were not included when the effective web.xml was logged.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.0.M1 through 9.0.118, from 8.5.0 through 8.5.100. Other versions that have reached end of support may also be affected.
Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119 which fixes the issue.
Detection of Error Condition Without Action vulnerability in Apache Tomcat when configuring CRLs for a FFM based connector.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M7 through 10.1.55, from 9.0.83 through 9.0.118.
Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119, which fixes the issue.
Always-Incorrect Control Flow Implementation vulnerability in Apache Tomcat's rewrite valve meant that if the first condition in an OR chain matched, subsequent non-OR conditions were skipped.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.0.M1 through 9.0.118, from 8.5.0 through 8.5.100. Other versions that have reached end of support may also be affected.
Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119, which fix the issue.
Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) vulnerability in the number guess example for Apache Tomcat.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.0.M1 through 9.0.118, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other versions that have reached end of support may also be affected.
Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119, which fix the issue.