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DISK OF DECEPTION

Mount disk images, locate covert image files, and decode hidden binary messages encoded via Unicode zero-width space characters.

Tools Used

mountbinwalkPython

Overview

We are given a compressed disk image file. After extraction and mounting the loopback device, we browse the files.

Reconnaissance

We identify flag.jpeg mirrored across multiple directories. Standard file metadata analysis yields no results, but printing text contents shows strange, invisible strings.

Exploitation Strategy

The file contents hide Unicode zero-width characters (ZWSP, ZWNJ, ZWJ) which map to binary 1s and 0s. A Python script is created to parse and convert these characters back into ASCII.

Solution Code

# Unicode Zero-Width character decoding
# ZWSP (\u200b) -> '0'
# ZWNJ (\u200c) -> '1'
# Decode binary stream back to ASCII characters to obtain: Kaal{Y0U_AR3_0N_R!GHT_PL4C3}

Flag

Kaal{Y0U_AR3_0N_R!GHT_PL4C3}