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S C E N A R I O
A Linux environment is running with three users: play_1, play_2, and ttyduser, all sharing the same password (1234). In the background, a monitoring script (/run.sh) continuously scans system processes for a specific privilege mismatch condition. If a process is detected where the real user is play_1 and the effective user is play_2, the system automatically copies a sensitive file (/root/flag.txt) to /flag.txt. The challenge is to manipulate process credentials in order to trigger this condition and retrieve the flag.

O B J E C T I V E
Exploit Linux process credential behavior by understanding real user ID and effective user ID differences. Create and execute a binary that runs under a mismatched credential context (RUID vs EUID) so that the monitoring script detects it. Once triggered, retrieve the flag from /flag.txt.
Flag Format: Flag{}

Infrastructure We Terminal 
Provided Files Access to system with users play_1, play_2, ttyduser
Tools Linux Terminal, GCC
Flag Format Flag{}