A c-ares security update has been released for Ubuntu Linux 20.10.

USN-4638-1: c-ares vulnerability

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Ubuntu Security Notice USN-4638-1
November 19, 2020

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

- Ubuntu 20.10

Summary:

c-ares could be made to denial of service if it received a specially crafted
DNS request.

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

Details:

It was discovered that c-ares incorrectly handled certain DNS requests.
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 20.10:
libc-ares2 1.16.1-1ubuntu0.1

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

References:
  https://usn.ubuntu.com/4638-1
CVE-2020-8277

Package Information:
  https://launchpad.net/ubuntu/+source/c-ares/1.16.1-1ubuntu0.1