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

Working on the assumption that the parameter you are targeting is being

appended to a preset directory specified by the application, modify the

parameter’s value to insert an arbitrary subdirectory and a single traver-

sal sequence. For example, if the application submits the parameter

file=foo/file1.txt

then try submitting the value

file=foo/bar/../file1.txt

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Chapter 10 

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Exploiting Path Traversal

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HACK STEPS (continued)

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If the application’s behavior is identical in the two cases, then it may be

vulnerable. You should proceed directly to attempting to access a differ-

ent file by traversing above the start directory.

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