USN-4233-2: GnuTLS update

23 January 2020

USN-4233-1 marked SHA1 as untrusted in GnuTLS with no workaround.

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Releases

Packages

Details

USN-4233-1 disabled SHA1 being used for digital signature operations in
GnuTLS. In certain network environments, certificates using SHA1 may still
be in use. This update adds the %VERIFY_ALLOW_BROKEN and
%VERIFY_ALLOW_SIGN_WITH_SHA1 priority strings that can be used to
temporarily re-enable SHA1 until certificates can be replaced with a
stronger algorithm.

Original advisory details:

As a security improvement, this update marks SHA1 as being untrusted for
digital signature operations.

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

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

Ubuntu 18.04
Ubuntu 16.04

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