challenges
Game 21
We have a JPEG image to analyze. Check its properties:
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| ❯ file monitor.jpg
monitor.jpg: JPEG image data, Exif standard: [TIFF image data, little-endian, direntries=11, description=SAMSUNG, ...], baseline, precision 8, 640x480, components 3
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Check for embedded data with binwalk:
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| ❯ binwalk monitor.jpg
Analyzed 1 file for 85 file signatures (187 magic patterns) in 9.0 milliseconds
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Attempting to use stegseek reveals a structural
issue:
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| ❯ stegseek monitor.jpg
StegSeek 0.6
Invalid JPEG file structure: two SOI markers
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The file contains multiple JPEG images (indicated by multiple Start
of Image markers). Extract them using foremost:
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| ❯ foremost monitor.jpg
❯ tree output/
output/
├── audit.txt
└── jpg
├── 00000000.jpg
├── 00000383.jpg
├── 00000765.jpg
├── 00001148.jpg
├── 00001532.jpg
├── 00001914.jpg
├── 00002297.jpg
└── 00002681.jpg
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Examine the extracted images to find the flag.
H4CC3R_IN_TH3_MIDD33_4TT4CK