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sys-team_172267's avatar
sys-team_172267
Icon for Nimbostratus rankNimbostratus
Mar 10, 2016

Blocking specific "USER AGENT" version and lower by iRule

Hello,   i want to use iRule to block requests that contain some "USER AGENT" version and lower("=<").   how can i do it?   Thanks.  
iRules
LTM
security
user agent
Kai_Wilke's avatar
Kai_Wilke
Icon for MVP rankMVP
Mar 11, 2016

Hi Sys-team,

I'm afraid, you can't block user-agents by using a "version < X" syntax. You have to block them one-by-one by using 

-glob
wildcard matches.

Example to block Internet Explorer below v11:

when HTTP_REQUEST {
    switch -glob -- [HTTP::header value "User-Agent"] "*MSIE 2*" - "*MSIE 3*" - "*MSIE 4*" - "*MSIE 5*" - "*MSIE 6*" - "*MSIE 7*" - "*MSIE 8*" - "*MSIE 9*" - "*MSIE 10*" {
        HTTP::respond 200 content "Unsupported Brwoser"
    }
}

Note: A great source for user-agent string values can be found here... http://www.useragentstring.com/pages/useragentstring.php

Cheers, Kai