USN-8383-1: Tomcat vulnerabilities

Publication date

4 June 2026

Overview

Several security issues were fixed in Tomcat.


Packages

Details

It was discovered that Tomcat incorrectly handled digest
authentication. A remote attacker could possibly use this issue to
bypass authentication restrictions. (CVE-2026-43512)

It was discovered that Tomcat incorrectly handled case sensitivity
in LockOutRealm. A remote attacker could possibly use this issue to
bypass account lockout protections and obtain sensitive information.
(CVE-2026-43513)

It was discovered that Tomcat incorrectly handled authorization when
multiple method constraints defined the same HTTP method. A remote
attacker could possibly use this issue to bypass authorization
restrictions. (CVE-2026-43515)

It was discovered that Tomcat incorrectly handled digest
authentication. A remote attacker could possibly use this issue to
bypass authentication restrictions. (CVE-2026-43512)

It was discovered that Tomcat incorrectly handled case sensitivity
in LockOutRealm. A remote attacker could possibly use this issue to
bypass account lockout protections and obtain sensitive information.
(CVE-2026-43513)

It was discovered that Tomcat incorrectly handled authorization when
multiple method constraints defined the same HTTP method. A remote
attacker could possibly use this issue to bypass authorization
restrictions. (CVE-2026-43515)

Update instructions

After a standard system update you need to restart Tomcat to make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
16.04 LTS xenial libtomcat7-java –  7.0.68-1ubuntu0.4+esm4
tomcat7 –  7.0.68-1ubuntu0.4+esm4
14.04 LTS trusty libtomcat6-java –  6.0.39-1ubuntu0.1+esm3  
libtomcat7-java –  7.0.52-1ubuntu0.16+esm2  
tomcat6 –  6.0.39-1ubuntu0.1+esm3  
tomcat7 –  7.0.52-1ubuntu0.16+esm2  

Reduce your security exposure

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