The Web Application Hacker’s Handbook Discovering and Exploiting Security Flaws

Continued

Chapter 10 

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Exploiting Path Traversal

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HACK STEPS (continued)

On Unix-based platforms, files that root may not write are version-

dependent, but attempting to overwrite a directory with a file should 

always fail, so you can try:

../../../../../../../../../../../../tmp/writetest.txt 

../../../../../../../../../../../../tmp

For each pair of tests, if the application’s behavior is different in response

to the first and second requests (for example, if the second returns an error

message, while the first does not), then it is likely that the application is

vulnerable.

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