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Forum Discussion

ScottA_6475's avatar
ScottA_6475
Icon for Nimbostratus rankNimbostratus
Mar 14, 2012

Custom rule to detect no User-Agent:

I am trying to create a custom ASM rule to determine if no user-agent string has been defined in the HTTP header. This seems like a simple task, but I can't get it to work. Here is what I have:

 

 

content:!"User-Agent|3A|";

 

 

app sec
BIG-IP Access Policy Manager (APM)
security

1 Reply

  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Mar 17, 2012
    Hi Scott,

     

     

    The simplest option I can think of is to set User-Agent as a required header (under Policy | Headers | Mandatory Headers).

     

     

    If you want to block if the User-Agent (and all other) header(s) are present with no value, you could set 'Header name with no header value' for blocking.

     

     

    Aaron