Official LostKey Discussion

Official discussion thread for LostKey. Please do not post any spoilers or big hints.

Comments

  • So I know what the program is, but just not how to crack it.
  • edited September 2020

    What curve is that? I've scoured wiki and EFD to no avail.
    I've found implementation bug (?) and the assertion says nothing about the the field order either.

    Hack The Box

  • A pretty good, fun challenge! Harder than I expected, but I learnt a lot on the way. Without giving away too much, you need to work out the curve, it’s not your typical EC. Then SageMath is your friend...

  • Need some help here, I found nothing interesting in the python code until now....

  • Type your comment> @Agatuz1 said:

    Need some help here, I found nothing interesting in the python code until now....

    Have you worked out the curve yet?

  • Type your comment> @jack0 said:

    Type your comment> @Agatuz1 said:

    Need some help here, I found nothing interesting in the python code until now....

    Have you worked out the curve yet?

    Yes, I found the curve parameters, and found the y coord for the Gn. but now I am totally stuck.
    Can I PM you?

  • Such a great challenge! Thanks @R4J! Thanks to @jack0 for the nudge!
    If anyone needs a small hint or a sanity check they can send me a pm!

    ArtemisFY
    OSCP

  • Type your comment> @Agatuz1 said:

    Yes, I found the curve parameters, and found the y coord for the Gn. but now I am totally stuck.
    Can I PM you?

    Sure

  • Oh man, this is my new favorite challenge. Thanks to ArtemisFY and jack0 for the nudges, and sampriti for creating it. I knew nothing about ECC or sage before starting this, and it was a very educational journey. Andrea Corbellini's blog has a good "gentle introduction" to the field if you are starting from nothing. The Hankerson, Menezes, and Vanstone textbook is more comprehensive. Feel free to PM for nudges, and Merry Christmas, everybody.

Sign In to comment.