1. Ubuntu Security Notices
  2. USN-5732-1

USN-5732-1: Unbound vulnerability

Publication date

17 November 2022

Overview

Unbound could be made to stop responding if it received specially crafted network traffic.

Releases

Packages

  • unbound - validating, recursive, caching DNS resolver

Details

It was discovered that Unbound incorrectly handled delegations with a large
number of non-responsive nameservers. A remote attacker could possibly use
this issue to cause Unbound to consume resources, leading to a denial of
service.

It was discovered that Unbound incorrectly handled delegations with a large
number of non-responsive nameservers. A remote attacker could possibly use
this issue to cause Unbound to consume resources, leading to a denial of
service.

Update instructions

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

Learn more about how to get the fixes.

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

Ubuntu Release Package Version
22.10 kinetic unbound –  1.16.2-1ubuntu0.1
libunbound8 –  1.16.2-1ubuntu0.1
22.04 jammy unbound –  1.13.1-1ubuntu5.3
libunbound8 –  1.13.1-1ubuntu5.3
20.04 focal unbound –  1.9.4-2ubuntu1.4
libunbound8 –  1.9.4-2ubuntu1.4
18.04 bionic libunbound2 –  1.6.7-1ubuntu2.6
unbound –  1.6.7-1ubuntu2.6

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References

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