A XMLTooling security update has been released for Ubuntu Linux 16.04 LTS.

[USN-6274-1] XMLTooling vulnerability

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Ubuntu Security Notice USN-6274-1
August 03, 2023

xmltooling vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 16.04 LTS (Available with Ubuntu Pro)

Summary:

XMLTooling could be made to allow for unintended server side actions
if it received specially crafted input.

Software Description:
- xmltooling: C++ XML parsing library with encryption support

Details:

Jurien de Jong discovered that XMLTooling did not properly handle certain
KeyInfo element content within an XML signature. An attacker could possibly
use this issue to achieve server-side request forgery.

Update instructions:

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

Ubuntu 16.04 LTS (Available with Ubuntu Pro):
  libxmltooling6v5                1.5.6-2ubuntu0.3+esm1

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

References:
  https://ubuntu.com/security/notices/USN-6274-1
  CVE-2023-36661