Home / mailings

PDF

[USN-8551-1] Tomcat vulnerabilities

Posted on 15 July 2026
Ubuntu Security

==========================================================================Ubuntu Security Notice USN-8551-1
July 15, 2026

tomcat8 vulnerabilities
==========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

Several security issues were fixed in Tomcat.

Software Description:
- tomcat8: Servlet and JSP engine

Details:

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 the Tomcat number guess example application did
not properly sanitize user-supplied input. An attacker could possibly
use this issue to inject malicious scripts, resulting in cross-site
scripting. (CVE-2026-50229)

It was discovered that Tomcat incorrectly evaluated rewrite valve
conditions in certain configurations. An attacker could possibly use
this issue to bypass rewrite rules, resulting in unauthorized access.
(CVE-2026-53404)

It was discovered that Tomcat incorrectly omitted certain authorization
information when logging the effective web.xml configuration. An
attacker could possibly use this issue to hide authorization
constraints, resulting in reduced auditability. (CVE-2026-55276)

Update instructions:

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

Ubuntu 18.04 LTS
libtomcat8-embed-java 8.5.39-1ubuntu1~18.04.3+esm6
Available with Ubuntu Pro
libtomcat8-java 8.5.39-1ubuntu1~18.04.3+esm6
Available with Ubuntu Pro
tomcat8-examples 8.5.39-1ubuntu1~18.04.3+esm6
Available with Ubuntu Pro

Ubuntu 16.04 LTS
libtomcat8-java 8.0.32-1ubuntu1.13+esm2
Available with Ubuntu Pro
tomcat8-examples 8.0.32-1ubuntu1.13+esm2
Available with Ubuntu Pro

In general, a standard system update will make all the necessary changes.

References:
https://ubuntu.com/security/notices/USN-8551-1
CVE-2026-43515, CVE-2026-50229, CVE-2026-53404, CVE-2026-55276

--===============6764024276481672382==Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: OpenPGP digital signature

 

TOP