An OpenLDAP security update has been released for Ubuntu 14.04 LTS, 16.04 LTS, and 18.04 LTS.

[USN-6197-1] OpenLDAP vulnerability

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Ubuntu Security Notice USN-6197-1
July 03, 2023

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

- Ubuntu 18.04 LTS (Available with Ubuntu Pro)
- Ubuntu 16.04 LTS (Available with Ubuntu Pro)
- Ubuntu 14.04 LTS (Available with Ubuntu Pro)

Summary:

OpenLDAP could be made to crash if it received specially crafted
input.

Software Description:
- openldap: Lightweight Directory Access Protocol

Details:

It was discovered that OpenLDAP was not properly performing bounds checks
when executing functions related to LDAP URLs. An attacker could possibly
use this issue to cause a denial of service.

Update instructions:

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

Ubuntu 18.04 LTS (Available with Ubuntu Pro):
  slapd                           2.4.45+dfsg-1ubuntu1.11+esm1

Ubuntu 16.04 LTS (Available with Ubuntu Pro):
  slapd                           2.4.42+dfsg-2ubuntu3.13+esm2

Ubuntu 14.04 LTS (Available with Ubuntu Pro):
  slapd                           2.4.31-1+nmu2ubuntu8.5+esm6

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

References:
  https://ubuntu.com/security/notices/USN-6197-1
  CVE-2023-2953