Vulnerability Mitigation

Hi  ,

Yes you can mitigate it (or restrict access to URLs using allowed domains ) using iRules also where you will allow request coming for specific domain/URL only. Below is the sample iRule where it is allowing all the requests coming for *.abc.com and *.xyz.com domains.

Now here you can mentioned specific FQDNs as well e.g. mysite.abc.com or mysite.xyz.com. So its upto you how do you want to have your iRule. Additionally I have added statements to log the requests. This will give you visibility to the dropped requests as well. 

when HTTP_REQUEST {
 
if {([HTTP::host] contains "abc.com") || 
    ([HTTP::host] contains "xyz.com")
   
} {
 
        log local0. "Allowed Hostname:[HTTP::host]"
} else {
 
    drop
    log local0. "“Invalid hostname: [HTTP::host]"
}
}

Hope it helps!