High severity · published Aug 25, 2026
CVE-2026-68569
Apache Tomcat: Principal lookup can fail open in some cases
8.1
CVSS
0.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TO
Tomcat · Apache
11.0.0-M1 through 11.0.24; 10.1.0-M1 through 10.1.57; 9.0.0.M1 through 9.0.120; 8.5.0 through 8.5.100; 7.0.0 through 7.0.109 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-68569
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-68569
Mailing List
https://lists.apache.org/thread/8robqo76q0osxgw0b5lcwgz0hcf9h4zc
Mailing List
http://www.openwall.com/lists/oss-security/2026/08/26/8
More from Tomcat
9.8
CVE-2025-24813
Apache Tomcat: Potential RCE and/or information disclosure and/or information corruption with partial PUT
9.8
CVE-2020-1938
Apache Tomcat Improper Privilege Management Vulnerability
9.8
CVE-2016-8735
Remote code execution is possible with Apache Tomcat before 6.0.48, 7.x before 7.0.73, 8.x before 8.0.39, 8.5.x before 8.5.7, and 9.x before 9.0.0.M12 if…
8.1
CVE-2017-12617
When running Apache Tomcat versions 9.0.0.M1 to 9.0.0, 8.5.0 to 8.5.22, 8.0.0.RC1 to 8.0.46 and 7.0.0 to 7.0.81 with HTTP PUTs enabled (e.g
8.1
CVE-2017-12615
When running Apache Tomcat 7.0.0 to 7.0.79 on Windows with HTTP PUTs enabled (e.g