Knowledge sharing: Version 10 no 7 byte limit for sinatures examples for Layer 7 (L7) DDOS/Brute force protection and referer match
You can check my previous discussions for this for making a vuntability signature that will block Application level DDOS or Brute force on a login page:
https://live.paloaltonetworks.com/t5/general-topics/the-7-byte-custom-signature-minimum/m-p/3873
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