EquationSolver (exp60)
I created a program for an unsolveable equation system. My friend somehow forced it to solve the equations. Can you tell me how he did it?
File Checker (rev60)
My friend sent me this file. He told that if I manage to reverse it, I’ll have access to all his devices. My misfortune that I don’t know anything about reversing :/
FlagStore (exp70)
Here’s the ultimate flag store. Store and retrieve your flags whenever you want.
It’s Prime Time! (code60)
Description: We all know that prime numbers are quite important in cryptography. Can you help me to find some?
Service: 188.166.133.53:11059
Running netcat against the address gave the following output:
> nc 188.166.133.53 11059 Hi, you know that prime numbers are important, don't you? Help me calculating the next prime! Level 1.: Find the next prime number after 5:
I haven’t done much work with Ruby, but this little challenge from the Internetwache CTF looked interesting.
Ruby’s count (exp50)
Description: Hi, my name is Ruby. I like converting characters into ascii values and then calculating the sum.
Service: 188.166.133.53:12037
The first thing to do was to poke the service using netcat:
> nc 188.166.133.53 12037
Let me count the ascii values of 10 characters:
> 123
WRONG!!!! Only 10 characters matching /^[a-f]{10}$/ !