Tryhackme Lfi Walkthrough

Local File Inclusion vulnerabilieis entail when a user inputs contains a file path which results in retrieval of unintended system files via a web service.

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Access Web Server

connect to

Accessing LFI point

Within URL input fields request containing ?file= can optionally be used to read arbitrary files within the system. To which private files such as passwords, ssh keys along side an array of data can be retrieved by an attacker.

Navigating the page, after click the “Leave a Review” button yeilded a field in the address bar og /home?page=about

Testing LFI Point

At this point utilzing a request such as ../../../../etc/passwd testing if request is returned:

To which at the bottom of the page yielded the /etc/passwd file. From the information gathered from the “passwd” file we can find a user name “Falcon”

Retrieveing falcon .bashrc

The .bashrc file contains imporatin inforatmin in regards to the shell of the user falcon. Calling the file from the LFI to enumerate falcon users shell:


Capturing falcons ssh key

Using the LFI the id_rsa of the user can be returned from the /home/falcon/.ssh/id_rsa directory

Switched over to burp to capture the request of the id_rsa

save the contents of the id_rsa to a file: Falcon_id_rsa

Change the chmod to 600 and access ssh as falcon:

chmod 600 falcon_id_rsa
ssh -i falcon_id_rsa [email protected]

Escalate from falcon to root

Check if user falcon has any sudo abilities:

sudo -l

GTFObins for journalctl - states to launch the binary and type !/bin/sh