Posts Categorized / CTF
During the Hack in the Box Amsterdam 2015 conference (28,29 May 2015) we participated for the 3rd time in a row with team Hack.ERS in the CTF game. Once again the team included both me and Gijs from the Eindbazen team and Riley as the 3rd player. Multiple other Eindbazen members organized the CTF just as in the […]
Last weekend ASIS CTF took place and we (the Eindbazen team) spend some hours playing it. While we did not play the whole weekend we did solve some of the challenges. Since I enjoyed the challenges I worked on I decided to create these write-ups of them.
During the Hack in the Box Amsterdam 2014 conference we participated with the Hack.ERS team of Deloitte in the CTF game. The team included both me and Gijs from the Eindbazen team, while multiple other Eindbazen members organized the CTF. While this might sounds weird it actually meant that the organizing Eindbazen really liked to […]
With the Eindbazen CTF team, we hosted the CTF (ebCTF) during the hackers event OHM2013. To generate some awareness about the CTF and OHM2013 event we also held a Teaser round some time before it. Besides full-filling an organizers role I also created multiple challenges for both the teaser round and the CTF. For the teaser round I created […]
More than two years ago I worked on meaningful MD5 collisions, especially creating executables files, but I never finished my write up about this until now (hurray for having a sabbatical 😉 ). The idea behind this project was to create multiple executables with the same MD5, but with different behavior. I ended up creating […]
This long delayed article is a write-up of the Swiss Cyber Storm Social Challenge which took place on May 14, 2011. Because of lack of time I simply did not finish this article earlier, however since I really enjoyed the challenge I decided to release it anyways, even though it is a bit dated now.
During the recent Defcon 19 CTF pre-qualifications, one of the challenges included to connect ‘quicker’ to a web server. While figuring out what the solution was for this challenge one of the things I tried was to send the HTTP GET request already in the TCP handshake stage. Sadly enough this had nothing to do […]
This article is a write-up of the Swiss Cyber Storm CarGame Challenge 5 (March/April 2011). For more info on the Swiss Cyber Storm Conference please check my post about the conference here. I only joined the CarGame in level 4 (my write-up for level 4 can be found here), which meant I could not qualify […]
This article is a write-up of the Swiss Cyber Storm CarGame Challenge 4 (February 2011). For more info on the Swiss Cyber Storm Conference please check my post about the conference here. I only joined the CarGame in level 4, which meant I could not qualify any more to play the CarGame challenge during the […]