DEF CON Quals 2017: beatmeonthedl

david@systemoverlord.com (David Tomaschik) — Sun, 30 Apr 2017 00:00:00 +0000

I played in the DEF CON quals CTF this weekend, and happened to find the challenge beatmeonthedl particularly interesting, even if it was in the “Baby’s First” category. (DC Quals Baby’s Firsts aren’t as easy as one might think…)

So we download the binary and take a look. I’m using Binary Ninja lately, it’s a great tool from the Vector35 guys, and at the right price compared to IDA for playing CTF. :) So I open up the binary, and notice a few things right away. This is an x86-64 ELF binary with essentially none of the standard security features enabled:

Writeup on System Overlord

DEF CON Quals 2017: beatmeonthedl