A libntlm security update has been released for Ubuntu Linux 18.04 LTS and 20.04 LTS.

USN-5108-1: libntlm vulnerability

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Ubuntu Security Notice USN-5108-1
October 08, 2021

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

- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS

Summary:

libntlm could be made to crash or possibly execute arbitrary code.

Software Description:
- libntlm: NTLM authentication library

Details:

It was discovered that Libntlm incorrectly handled specially crafted NTML
requests. An attacker could possibly use this issue to cause a denial of
service or another unspecified impact.

Update instructions:

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

Ubuntu 20.04 LTS:
libntlm0 1.5-2ubuntu0.1

Ubuntu 18.04 LTS:
libntlm0 1.4-8ubuntu0.1

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

References:
  https://ubuntu.com/security/notices/USN-5108-1
CVE-2019-17455

Package Information:
  https://launchpad.net/ubuntu/+source/libntlm/1.5-2ubuntu0.1
  https://launchpad.net/ubuntu/+source/libntlm/1.4-8ubuntu0.1