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THE IMPOSSIBLE ROAD

Reverse engineering a Windows PE to reconstruct a Telegram Bot Token API call for flag extraction.

Tools Used

x64dbgstringspython

Overview

We are given a Windows command-line game executable named game.exe.

Reconnaissance

Extracting strings from the executable reveals Telegram bot API endpoints (/getUpdates) and fragmented token strings.

Exploitation Strategy

By analyzing assembly instructions in the score validation logic, we reconstruct the Telegram bot ID and token suffix. Querying the Telegram API directly retrieves the flag from channel updates.

Solution Code

# Reconstructed Telegram Bot Token:
# 8597443944:AAHKhN_WqZelcbtnjiD68ONqvyNe6Z7TRGc
# Query URL:
# https://api.telegram.org/bot8597443944:AAHKhN_WqZelcbtnjiD68ONqvyNe6Z7TRGc/getUpdates?limit=5
# Flag: Kaal{Sp33d_1s_K3y_t0_Fr33d0m}

Flag

Kaal{Sp33d_1s_K3y_t0_Fr33d0m}