Official signup Discussion

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

It does not look like it, but the solution involves little math! I felt scammed at first, but in the end it was fun and I learnt a lot anyway :smiley:

can anyone give me a nudge ,i know some method to solve this, but its impractical ,iam i missing something ?

Managed to get the key in an unintended way, but at least it allowed me to use the flag to check out some writeups showing how it is intended to be solved.
Looking at the code again, it really does not look like the potential for this kind of exploit, it just looks like we got unbelievably lucky. The fact that there did not seem to be any potential problem in the signing algorithm is the reason I went with the other approach.