An OpenLDAP security update has been released for Ubuntu 20.04 LTS, 19.10, 18.04 LTS, and 16.04 LTS.

USN-4352-1: OpenLDAP vulnerability

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Ubuntu Security Notice USN-4352-1
May 06, 2020

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

- Ubuntu 20.04 LTS
- Ubuntu 19.10
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

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

Software Description:
- openldap: Lightweight Directory Access Protocol

Details:

It was discovered that OpenLDAP incorrectly handled certain queries. A
remote attacker could possibly use this issue to cause OpenLDAP to consume
resources, resulting in a denial of service.

Update instructions:

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

Ubuntu 20.04 LTS:
slapd 2.4.49+dfsg-2ubuntu1.2

Ubuntu 19.10:
slapd 2.4.48+dfsg-1ubuntu1.1

Ubuntu 18.04 LTS:
slapd 2.4.45+dfsg-1ubuntu1.5

Ubuntu 16.04 LTS:
slapd 2.4.42+dfsg-2ubuntu3.8

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

References:
  https://usn.ubuntu.com/4352-1
CVE-2020-12243

Package Information:
  https://launchpad.net/ubuntu/+source/openldap/2.4.49+dfsg-2ubuntu1.2
  https://launchpad.net/ubuntu/+source/openldap/2.4.48+dfsg-1ubuntu1.1
  https://launchpad.net/ubuntu/+source/openldap/2.4.45+dfsg-1ubuntu1.5
  https://launchpad.net/ubuntu/+source/openldap/2.4.42+dfsg-2ubuntu3.8