There are no IPS signatures for any ransomware types, that falls into the domain of the Anti-virus blade which has several signatures for Black Matter. You will want to use those if you have the Anti-Virus blade enabled.
While IPS was kind of the "original Threat Prevention" and had lots of signatures for things like eDonkey/Gator/Nimda and such, all that got cleaned up in R80 as many IPS signatures got migrated into the "proper" blades as described here: sk103766: List of IPS Protections removed in R8X.x. Although IPS still has a signature for the EICAR test virus to this day which I find perplexing...
But anyway if you can't or don't want to use the Anti-Virus blade for this, your best bet is to create a custom SNORT signature for your IPS blade matching Black Matter, I'm sure you could probably locate the proper SNORT rule(s) for it with a bit of research. All of the above is covered in my new IPS/AV/ABOT Immersion video series as well as Custom Threat Indicators (strongly preferred over the much older SNORT-based signatures) which you can't use in this case because they only function with AV and ABOT.
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