Apple has pushed an update to Gatekeeper

Apple had today pushed another update to Gatekeeper’s configuration data, bringing it to version 132. This should now be installed on all Macs running El Capitan, Sierra, and High Sierra.

As is normal, Apple does not release any details, although this usually reflects the latest revocations of developer certificates.

If you are running High Sierra and have not yet had this update installed – and shown in LockRattler (from Downloads above) – then I recommend that you contact Apple Support, and ask for their help to ensure that your Mac is properly updated.