A c-ares security update has been released for Ubuntu Linux 20.04 LTS.

[USN-6376-1] c-ares vulnerability

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Ubuntu Security Notice USN-6376-1
September 18, 2023

c-ares vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS

Summary:

c-ares could be made to crash if it received specially crafted network
traffic.

Software Description:
- c-ares: library for asynchronous name resolution

Details:

It was discovered that c-ares incorrectly parsed certain SOA replies. A
remote attacker could possibly use this issue to cause c-res to crash,
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:
libc-ares2 1.15.0-1ubuntu0.4

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

References:
https://ubuntu.com/security/notices/USN-6376-1
CVE-2020-22217

Package Information:
https://launchpad.net/ubuntu/+source/c-ares/1.15.0-1ubuntu0.4