Solutions to Puzzle #5 File Signatures- Advanced

Did you enjoy solving the first four File Signatures challenges? Now it’s time to check out how to solve the Advanced challenges. These are going to take a bit more work than just adding the right file extension!

Recap: download Puzzle5Files.zip and extract it to a Windows computer folder. Then for each file (1) figure out what software to use to open it successfully and (2) using the info in the files, answer the questions. The Advanced ones #5 ,#6 and #7 also have a flag hidden inside.

Just want the solution and the flag? Below is a short text version of the solutions or this video will provide a full walk-through.

File05 — There was an error in the File05 included in the download. It was supposed to have part of the header is missing — 66 74 79 70 6D 70 34 32. Once repaired, it can be opened successfully as an mp4 file. The flag is a caption on the screen about halfway through the video.
Q: What has black dots? Dalmatian puppies
FLAG:{Flag:pupp1es2L0ve}

File06 — is a pdf file BUT it has a zip file nested inside it. You need to extract the bytes belonging to the zip file, then unzip it to find the flag.
Q: What’s a matryoshka? Russian nested dolls
FLAG: {Flag: Th3reCanBe2in1}

File07 — is a doc file but it has text hidden at the end of the bytes
Q: Who’s there? a herd
FLAG: {D1dUcthisFlag?}