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OGN Challenge #6

This challenge can be found when Roanoke goes back to his office to watch the disk's content.

The Setup

We obtained an image of a disc drive. We've found that it uses a futuristic technology called "Blu-Ray", but we can't seem to get any video playing from the disc image itself.

Can you help us?

You'll find a disc image on the webpage, in the .iso disk format.

Reading the disk

When examining files that represent raw data (image, video, binary blob), a useful first step is to run strings on the document. strings will, according to its man page, print the sequences of printable characters in files.

$ strings DG_FINAL_PARTIAL_DUMP.ISO | grep key
ias=0 direct=3 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=24 scenecut=40 intra_refresh=0 rc_lookahead=50 rc=crf mbtree=1 crf=20.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_rati

$ strings DG_FINAL_PARTIAL_DUMP.ISO | grep KEY

No luck there. The challenge description mentions "Blu-Ray", so searching for more info is the next step. Searching "how to open bluray iso" reveals that VLC can open many Blu-Ray ISO files directly.

The flag appears in the VLC player immediately after opening the ISO file.