CVE-2026-68569: Apache Tomcat: Principal lookup can fail open in some cases

Severity: high (CVSS 8.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-25 · updated 2026-09-21
Weakness: CWE-287

Description

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 products

Apache Tomcat: from 7.0.0 through 7.0.109; from 8.5.0 before 9.0.121; from 10.1.0 before 10.1.58; from 11.0.0 before 11.0.25 — fixed in 10.1.58, 11.0.25, 9.0.121

How to fix

Upgrade to a fixed version: Apache Tomcat 10.1.58, 11.0.25, 9.0.121. Check the vendor advisory for mitigations.

References

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