I'm going to give you the same exact suggestions we (the community) would give for "random PPAs":
Only use trusted sources for Snaps (rather than 'random suggestions') and if you really are concerned, test in an isolated VM or other isolated system/sandbox before putting it on a production machine to see if the snap does anything 'malicious'.
Beyond this step, there's no real way to properly 'vet' Snaps on the catalog for 'maliciousness'. If you find such a snap, though, you should report it to Canonical for immediate removal, and they can be pretty swift with that. (The same goes for PPAs, within 24 hours they can erase such a malicious PPA).