Exam 1Y0-340 topic 1 question 51 discussion

Scenario: A Citrix Engineer discovers a security vulnerability in one of its websites. The engineer takes a header trace and checks the Application Firewall logs.
The following was found in part of the logs:
method=GET request = http://my.companysite.net/FFC/sc11.html msg=URL length (39) is greater than maximum allowed (20).cn1=707 cn2=402 cs1=owa_profile cs2=PPE0 cs3=kW49GcKbnwKByByi3+jeNzfgWa80000 cs4=ALERT cs5=2015
Which type of Application Firewall security check can the engineer configure to block this type of attack?