Ubuntu Security Notice USN-4374-1
May 27, 2020
unbound vulnerabilities
==========================================================================
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 20.04 LTS
- Ubuntu 19.10
- Ubuntu 18.04 LTS
Summary:
Several security issues were fixed in Unbound.
Software Description:
- unbound: validating, recursive, caching DNS resolver
Details:
Lior Shafir, Yehuda Afek, and Anat Bremler-Barr discovered that
Unbound
incorrectly handled certain queries. A remote attacker could use
this issue
to perform an amplification attack directed at a target.
(CVE-2020-12662)
It was discovered that Unbound incorrectly handled certain
malformed
answers. A remote attacker could possibly use this issue to cause
Unbound
to crash, resulting in a denial of service. (CVE-2020-12663)
Update instructions:
The problem can be corrected by updating your system to the
following
package versions:
Ubuntu 20.04 LTS:
libunbound8 1.9.4-2ubuntu1.1
unbound 1.9.4-2ubuntu1.1
Ubuntu 19.10:
libunbound8 1.9.0-2ubuntu1.1
unbound 1.9.0-2ubuntu1.1
Ubuntu 18.04 LTS:
libunbound2 1.6.7-1ubuntu2.3
unbound 1.6.7-1ubuntu2.3
In general, a standard system update will make all the necessary changes.
References:
https://usn.ubuntu.com/4374-1
CVE-2020-12662, CVE-2020-12663
Package Information:
https://launchpad.net/ubuntu/+source/unbound/1.9.4-2ubuntu1.1
https://launchpad.net/ubuntu/+source/unbound/1.9.0-2ubuntu1.1
https://launchpad.net/ubuntu/+source/unbound/1.6.7-1ubuntu2.3
Read more https://packetstormsecurity.com/files/157840/USN-4374-1.txt

