Mar 27, 2026 - For details about updated CVE-2025-53521 (BIG-IP APM vulnerability), refer to K000156741.

Forum Discussion

Dianna_129659's avatar
Dianna_129659
Icon for Nimbostratus rankNimbostratus
May 02, 2014

F5 Blocking = Illegal Method: OPTIONS

F5 is set to learn and alarm. The Attack Type is Information Leakage. The Request Details indicates Illegal method for HTTP Method OPTIONS. The HTTP Request = OPTIONS / HTTP/1.1 I am trying to determ...
ASM Advanced WAF
management
security
Richard__Harlan's avatar
Richard__Harlan
Historic F5 Account
May 02, 2014

When a systems send a Option command it is asking the server what methods do you support/allow. The server will respond with methods like GET/POST/HEAD and such.

 

MSZ's avatar
MSZ
Icon for Nimbostratus rankNimbostratus
Aug 21, 2017

Which method we can use ACT as Method instead of OPTION method? Please