How to Block/Allow Custom Extensions using RegEx?

MetaDefender Core allows blocklisting and allowlisting based on both the FileType and Filename.

However, for custom extensions, it may be possible these are not listed within the FileType category, in which case you can create a rule using RegEx to achieve the desired result.

For example, for a .dat extension, which is not a standard one, but rather depends on the software that generates it, you will not find it under FileType. You can then use the filename option and create a rule as in the example below:

This is a case-insensitive pattern that will block all the files ending in .dat .