Musee du Louvre (50)

Description

Write Up

If we open it with Hex Editor, we will see that it is a JPEG file, so it should start with the hex FF D8 and end with FF D9 (see JPEG File format structure). But we see the file end with the ascii IEND which maps to a PNG file.

If we search for the hex FF D9 we will see that it is appended with 0x89 and then PWN, while for a PNG file it should be 0x89 and PNG, so if we just change it to PNG and then copy the remaining to a new file, we will see the image showing the flag: COMPFEST9{dont_trust_the_end}