Hi @EMTUser!
Thanks for reaching out! This error is caused by older versions of snort which are not able to handle more current rule logic. We recently released a list of our supported snort engines here which I’d recommend reviewing if you are running older than snort-2.9.13 to avoid similar errors in the future.
I’ve updated this rule so that it should work with older versions but please let me know if you have issues after today’s release and we can try to figure out a solution.
Thanks!
Isaac