CVE-2026-68569: Apache Tomcat: Principal lookup can fail open in some cases
Improper Authentication vulnerability in Apache Tomcat meant that in some circumstances (e.g. CLIENT-CERT, SPNEGO) that a user would be authenticated even if the user did not exist in the DataSourceRealm.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.24, from 10.1.0-M1 through 10.1.57, from 9.0.0.M1 through 9.0.120.
The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other unsupported versions may also be affected.
Users are recommended to upgrade to version 11.0.25, 10.1.58 or 9.0.121, which fix the issue.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 11.0.25 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.1.58 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 9.0.121
Event History
Frequently Asked Questions
Which deployments are exposed to this issue?
Deployments using Apache Tomcat with DataSourceRealm are exposed when authentication occurs under circumstances such as CLIENT-CERT or SPNEGO. The affected supported release ranges are Tomcat 11.0.0-M1 through 11.0.24, 10.1.0-M1 through 10.1.57, and 9.0.0.M1 through 9.0.120.
What does an attacker need to exploit the authentication failure?
The issue can authenticate a user even when that user does not exist in DataSourceRealm. The provided information identifies CLIENT-CERT and SPNEGO as example authentication circumstances where this can occur.
What versions remediate the issue?
Upgrade to Tomcat 11.0.25, 10.1.58, or 9.0.121. Tomcat 8.5.0 through 8.5.100 and 7.0.0 through 7.0.109 are also known affected but were end of life when the CVE was created.