What does HackerNews think of picklescan?
Security scanner detecting Python Pickle files performing suspicious actions
Pondering on whether to keep proceeding trying this out or not...
EDIT: a scan with picklescan[0] found nothing.. exciting.
There are tools to check the format for suspicious behaviour: https://github.com/mmaitre314/picklescan seems to be the most developed one.
You can also check the format manually (being careful not to call into it), like demonstrated by this more rudimentary scanner: https://github.com/zxix/stable-diffusion-pickle-scanner
It you do check for security issues yourself, you'll need to read up on what magical methods/variables may cause code execution. Simple demonstrations of dangerous code can be found all over the web (https://stackoverflow.com/questions/47705202/pickle-exploiti...) but I'm sure there are obfuscation tricks that simple scans won't catch.