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.
The team name I came up with was 0x7c_Jake since I've been listening to a lot of Less than Jake ….. read on..?
"funsignals" was a 250 point binary exploitation challenge with 58 solves. The challenge itself was a very trivial example of sigreturn-oriented programming.
Sigreturn-oriented programming is a means of getting values into certain registers without having to use ROP gadgets that pop values from the stack. It's a technique that relies on how UNIX-like operating systems implement signals ….. read on..?