USN-4516-1: GnuPG vulnerability
It was discovered that GnuPG signatures could be forged when the SHA-1
algorithm is being used. This update removes validating signatures based on
SHA-1 that were generated after 2019-01-19. In environments where this is
still required, a new option –allow-weak-key-signatures can be used to
revert this behaviour.
Source: USN-4516-1: GnuPG vulnerability
