Well, the time has come for me to start the 8th set of the crypto challenges. Actually I have one remaining challenge to complete in set 7. I have started the work and have a good idea of what I am supposed to do, but I find the actual implementation a bit boring, so I have set it aside for now. The basic idea, as explained in the challenge itself, is to perform a series of bitwise operations to tweak bits in a message. After enough tweaks, we should have a new message that has the same MD4 hash (with a given probability).
Anyway, the authors of the challenges send the 8th set by email, and explicitly ask not to share the questions publicly. I am not sure if the same applies to the solutions; I asked them, but have received no reply so far. In the meantime they will be on a private repository.
I will miss doing the writeups of the most intriguing solutions. So I guess you’ll see less new posts here. I however occasionally hang out in #cryptopals on Freenode, and unofficial channel for these challenges.