0ops CTF Qualifiers 2015 - Vezel - Mobile Challenge

I haven’t ever done a mobile challenge before so I thought I’d give this a try as it was one of the earliest challenges made available on the 0ctf site when it began. The clue was only this:

Securinets CTF Quals 2015 - aucun_choix Reversing Challenge

What a strange CTF this one was. Judging by all the comments on CTFtime a lot of people couldn’t get past the registration page. I myself registered ok, it was in French but Google translate got the message across. When I began the CTF I immediately noticed that this was a challenge for beginners. That’s great I do need to brush up on my basic skills.

BCTF 2015 - weak_enc Crypto challenge

After a challenging enough “Warm Up” challenge at BCTF2015 which involved cracking a poorly thought out RSA encryption, the next challenge we decided to tackle was the weak_enc challenge worth only 200 points. I don’t normally do crypto but the warmup challenge really got me in the mood so, here we go!

Our first time doing Vancouver BSides which was an event said to be aimed at beginners and students. I was expecting a fun and medium challenge but I found it to be trickier than expected and where I knew the general direction of the solutions for a number of problems I didn’t get enough time to focus on them during the middle of the week where it was held.

For this years CodeGate teams faced some ingenious challenges. Today I will write up the first challenge we solved which seems to have also been first for many of the teams. This challenge is Systemshock.