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Home FinalTrace 2025 Challenge Name - EXIF ECHOES
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Challenge Name - EXIF ECHOES

Challenge Name - EXIF ECHOES

  • Category: [Forensics/OSint]
  • Author: [ram]

Challenge Description

[This m0ment is more than it appears. Its very properties are… peculiar. Only by understanding its deepest whispers can you unlock the path.]

Solution

Initial Analysis

[As the challenge title suggests “EXIF,” the first step is to run exiftool on the image. This would reveal two unusual timestamps. The “echoes” hint at a combination of these two values.]

Tools Used

  • [exiftool]
  • [timestamp->epoch unix ( https://www.epochconverter.com/ ) ]
  • [ Hexadecimal XOR calculator (e.g., [https://xor.pw/] ]
  • [stegseek]

Step-by-Step Solution

Step 1: [Discover and Convert Timestamps]

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[exiftool m0ment.jpg]

[they scan exiftool, encounter a fake flag , which is a pastebin link which gives them sime vague hint ( btw bonus flag hidden as the authorname )(pastebin.com/r3LnLw4G ) ]

Step 2: [Generate the Passphrase via XOR]

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[# No command, but use a hex XOR calculator
# Input 1 (hex): 1681140600
# Input 2 (hex): 1727203620 
# Output (hex): 1a6343020]

[This step accomplishes the core trick of the challenge. By treating the two epoch values as hexadecimal numbers and XORing them, we generate the final passphrase (1a6343020) needed for extraction.]

Step 3: [Extract the Hidden File , and hence the flag]

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echo "1a6343020" > pass.txt
stegseek m0ment.jpg pass.txt
cat m0ment.jpg.out

[This command uses stegseek to rapidly test our generated password (1a6343020) against the image. stegseek confirms the password is correct and extracts the hidden file, saving it as m0ment.jpg.out.]

Flags

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CYS{b0nus_fl1g_686}
CYS{T1m3_Fr4gm3nt5_R3v34l_Th3_P4th}

Flag

CYS{T1m3_Fr4gm3nt5_R3v34l_Th3_P4th}
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