SB2026063006 - Authentication bypass in Apache Tomcat
Published: June 30, 2026
Security Bulletin ID
SB2026063006
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Improper authentication (CVE-ID: CVE-2026-55957)
CWE-ID: CWE-287 - Improper Authentication
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to bypass authentication.
The vulnerability exists due to improper authentication in JNDIRealm when authenticating binds using GSSAPI. A remote attacker can authenticate without providing the correct password to bypass authentication.
Remediation
Install update from vendor's website.
References
- https://tomcat.apache.org/security-10.html#Fixed_in_Apache_Tomcat_10.1.39
- https://github.com/apache/tomcat/commit/0cd21c0393b8811af22daddbba7b4e7328e2d79e
- https://tomcat.apache.org/security-11.html#Fixed_in_Apache_Tomcat_11.0.5
- https://tomcat.apache.org/security-9.html#Fixed_in_Apache_Tomcat_9.0.102