Can I make custom application signature for using referer of http header?

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Can I make custom application signature for using referer of http header?

Hello,

 

I would like to make custom application signature for using refer of http header. 

Can I ????

 

I made the follwoing signature. but PA is not detecting.

 

failed signature for referer.PNG

 

I would like to hear any your opinion and assistance.

 

Thanks,

KC Lee

 


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Good morning!

 

I usually work with custom threat signatures so I'm less familiar with the intricacies of custom application signatures.

 

However, I have a few pointers to try and help!

 

- There appears to be no space between Referer: and http. In most HTTP request headers, I see whitespace between the referer and it's contents, ie:

Referer: http://uquest\.u-quest\.net

 

- There is an unescaped special character in your pattern "-". According to page 37 of the Creating Custom Signatures document, "-" should be escaped with "\-" as it is a special character used for range expressions.

 

In addition to the two above points, when trying to troubleshoot a signature, I usually try to start from the most basic form of the signature to identify where in the process the signature is not working. In this case, removing the GET qualifier to test just that the pattern matching itself is functioning would be a good step to take in my opinion. Then, once the pattern match is working, add the qualifier back.

 

I hope this helps.

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L4 Transporter

Good morning!

 

I usually work with custom threat signatures so I'm less familiar with the intricacies of custom application signatures.

 

However, I have a few pointers to try and help!

 

- There appears to be no space between Referer: and http. In most HTTP request headers, I see whitespace between the referer and it's contents, ie:

Referer: http://uquest\.u-quest\.net

 

- There is an unescaped special character in your pattern "-". According to page 37 of the Creating Custom Signatures document, "-" should be escaped with "\-" as it is a special character used for range expressions.

 

In addition to the two above points, when trying to troubleshoot a signature, I usually try to start from the most basic form of the signature to identify where in the process the signature is not working. In this case, removing the GET qualifier to test just that the pattern matching itself is functioning would be a good step to take in my opinion. Then, once the pattern match is working, add the qualifier back.

 

I hope this helps.

View solution in original post

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@rcole

 

Thanks a lot.

Your advice is so helpful to me.

 

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