CVE-2026-29145
Apache Tomcat: Apache Tomcat: Authentication bypass due to CLIENT_CERT soft fail misconfiguration
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · April 10, 2026
Updated · September 30, 2026
Description
A flaw was found in Apache Tomcat and Apache Tomcat Native. When CLIENT_CERT authentication is configured with "soft fail" disabled, the authentication process may not correctly fail in certain scenarios. This vulnerability could allow an attacker to bypass expected client certificate authentication, potentially leading to unauthorized access to protected resources.
Statement
This Moderate vulnerability in Apache Tomcat and Apache Tomcat Native arises when CLIENT_CERT authentication is configured with "soft fail" disabled. This misconfiguration can lead to an authentication bypass, potentially allowing unauthorized access to protected resources. Red Hat Enterprise Linux versions 6, 7, 8, 9, and 10, along with Red Hat JBoss Web Server 5 and 6, are affected if running Apache Tomcat with this specific configuration.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
To mitigate this issue, ensure that CLIENT_CERT authentication is configured to strictly enforce client certificate validation. Review the Apache Tomcat conf/server.xml configuration. For SSLHostConfig or Connector elements, set the clientAuth attribute to required or ensure softFail is enabled if optional client certificate authentication is desired. A restart of the Apache Tomcat service is necessary for these configuration changes to apply.
CVSS / CWE
CVSS 3.1 · 5.9CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
CWE-303 · Incorrect Implementation of Authentication Algorithm