Example to detect SMTP 550 (destination email address does not exist)

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Example to detect SMTP 550 (destination email address does not exist)

L7 Applicator

Here is an example to alert when a server responds with SMTP 550 (mailbox does not exist). The context used is 'smtp-rsp-content' and the pattern to be matched is '550\ 5\.1\.1'.
<pattern>550\ 5\.1\.1</pattern>


Full example signature(7.0) attached 'sample_smtp_vulnerability_41002.xml'


Next, assume we would like to detect 10 triggers for this in a 60 second interval, we can create a combination brute force signature that looks for the signature created earlier:
<entry name="And Condition 1">
<entry name="Or Condition 1">


Full signature attached as 'sample_brute_vulnerability_41003.xml'.


For further information on custom signatures, please refer to the document at:

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