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Posts tagged with "capture-the-flag"

ret2emacs

April 14, 2022 ❖ Tags: writeup, capture-the-flag, emacs, binary-exploitation, heap-feng-shui

It's that time of year again where I take some time to reflect on UMass CTF. This is going to be shorter than last year's. I put out eight challenges, and I'm only going to be writing about one of them. Code, documentation, and write-ups for the others are available here.

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UMass CTF 2021 Postmortem

April 19, 2021 ❖ Tags: writeup, capture-the-flag

This was the first year our capture-the-flag event, UMass CTF 2021, was open to the public. The competition started Friday, March 26th at 18:00 EDT, and ended Sunday, March 8th at the same time. By the end of the competition, we had 1991 registered users, belonging to 1160 registered teams. No teams were tied, we had just one unsolved challenge, and each of the "harder" challenges had just one or two solves.

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UMass CTF 2020 - suckless Writeup

December 13, 2020 ❖ Tags: writeup, capture-the-flag, security, binary-exploitation, myrddin

Well, this is certainly overdue. It's the writeup for a challenge I authored for this year's UMass CTF, which ran from October 5th to October 12th. Yes, I'm late. But when you attend a university that tried very hard to squeeze the entire semester twelve weeks, you're going to deal with burnout and not nearly enough time to do things outside of your coursework. So I'm finally coming back to the challenge now that the semester's ended.

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Writeups for PlaidCTF 2019

April 14, 2019 ❖ Tags: writeup, security, reverse-engineering, capture-the-flag, x86, c, python

My long-lived hiatus from capture-the-flag has come to an end, as I got off my ass this weekend to play in PlaidCTF 2019. Being a one-man team is pretty lonely, but my old team wasn't playing, and even if they were, I don't know if I would've wanted to make the commute just to play with them.

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BackdoorCTF 2017: FUNSIGNALS

September 24, 2017 ❖ Tags: writeup, security, capture-the-flag, binary-exploitation, x86, linux

"funsignals" was a 250 point binary exploitation challenge with 58 solves. The challenge itself was a very trivial example of sigreturn-oriented programming.

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