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Example:  Anti-IDS Attack
• URL Forceful Browsing attempts on  “samples/admin” 
•
• Variations on a theme:
–Absolute Pathing: “samples/admin”
–Delimiter Padding: “samples///admin” 
–Relative Pathing: “samples/./admin“
–URL Encoding: "%2fsamples/admin“
–Path Traversal: “samples/fakedir/../admin“
–DOS Syntax: “samples\admin”
–tripe dots “samples/fakedir/.../admin”
–Null Method: "GET%00/samples/admin“
These are rather well known techniques, and signatures can be written for most of them.  But you have to know the signatures in order to write them.  Most of these type of attacks will still get through most security systems and never be seen.

These serve as examples to show variations on the same attack.  Combining any of these attacks or altering by adding characters (/ . \), or encoding ASCII values changes the attack pattern and can fool an IDS.