Apple has just pushed an update to Gatekeeper configuration data, which brings it to version 133.
As is usual, it does not announce the update, nor provide any information as to what changes it brings. However, this is likely to include further revocations of developer certificates which have become associated with malware, etc.
You can check whether this update has been installed by opening System Information via About This Mac, and selecting the Installations item under Software.
A full listing of security data file versions is given by LockRattler for Sierra and High Sierra, available from Downloads above.