I only kicked this off last night before bed, so I've just got up to see the result of the first task.

Challenge: Wallpaper

https://github.com/crackmesone/ctf-2026-challenges-public/tr...

    Duration:     4h 00m 15s
    Termination:  completed
    Verdict:      PARTIAL
    Confidence:   0.95

I'm using Kimi K3 as the evaluator because, again, Codex and co. wouldn't even evaluate the output. Kimi's verdict:

The agent reverse-engineered the 912-byte ELF, including the alphabet check, nibble state machine, move gate, and goal state.

It eventually produced:

    CMO{10012232101230103012333221101033210010}

I independently verified the underlying input against the actual binary:

    printf '10012232101230103012333221101033210010' |
        ./wallpaper/handout/wallpaper

which returns:

    good job, validate with CMO{your_input}

and exits 0.

The wrinkle is that the official answer key is:

    CMO{1012321103210033011233322110103321001}

So the puzzle apparently admits multiple accepted inputs. The agent found a valid password by reverse-engineering the program, but did not recover the canonical secret from the answer key.

I don't know why but your post was marked as [dead] for some reason. Just vouched for it.

Thanks! Might have been the multiple attempts at getting it to format nicely in a short amount of time.