Hi folks,
here is my Hackvent write-up. It was a really good CTF, but there was a really dump challenges. It was a challenge, where you called a number in switzerland. Also you needed a provider, who fakes the displaynumber of your calls. At the end I spend about 30€ to solve that challenge. If you want to try it by yourself, you can do it here. Remember, every try costs you round about 50 cent or something like this and calling robots are not so fast in the answer, like webservers ;)
Download: Hackvent 2016 - WriteUp (9650 Downloads)
Great job, thank you. Sadly i wasn’t able to solve last days challenge, but at least i know how it would have worked now. Awesome to see some different approaches.
My biggest problem was, that I was really impacient. The first things I tried was 17, 23 and 42. After I tried the 13 it doesn’t worked, because of connection issues and I think I pressed another number. So I really stucked on the second question.
Another bad decision was, that you needed a spoofing provider and you needed to pay the international telephone costs.
i dont know why there was so much trouble with the call…
some people got it with their first call, but the most people couldnt solve it…
1 3 3 7, so obvious…