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Tell HN: Come learn how to solve Stripe's Capture The Flag
- silverlight 15y agoAny chance this would be webcast live or recorded for later viewing?
- gdb 15y agoUnfortunately, we won't be webcasting. We will be releasing official solutions at some point however.
- tncardoso 15y agoI was going to ask the same question. It would be nice to see other people solutions too.
- mrmagooey 15y agoAwesome, I'm really looking forwards to these. I was stumped from level 1 and it made me worry about what I'm doing wrong/not doing for my own servers.
- karanlyons 15y agoThat's a little bit of a shame. I'm not close enough to make it to the meetup, but I and others would love some way to take part and chat with everyone.
- speednoise 15y agoI'd sign up in a heartbeat for a meetup like this in NYC.
- heywire 15y agoI'm so close on level06. If Real Life(TM) would just stop getting in the way, i'd be done by now :). I guess its going to be another late night...
- CZ-18 15y agoI sent an email after I beat it, but never got a response =(
- antonID 15y agoIf only this was Friday instead, I really wish I could make it, sounds like it would be interesting :(
- icebraining 15y agoMeh, I got to level 4 but didn't go any further. Learned a lot, but I'm still not sure if there wasn't a much simpler solution that I missed. Was return-to-libc really required to exploit it, or was I trying to kill a fly with a sledge hammer?
- mpakes 15y agoReturn-to-libc (a.k.a. ret2libc) is usually used to bypass NX-bit / DEP, but NX was disabled for level04 - the solution does not require return-to-libc.
- icebraining 15y agoBut it did have ASLR enabled, right? I didn't get how to bypass that without ret2libc. I think I'll try again tomorrow morning and see what I missed.
- mpakes 15y agoASLR is enabled, yes. ASLR actually makes ret2libc much more difficult to pull off (esp. on 64-bit platforms), because the location of libc.so itself is randomized.
- rzhou 15y agoOn 32-bit machines, you can disable mmap randomization (and thus library randomization) using ulimit -s unlimited. Also, there's another useful place you can return to that isn't in libc.
- mpakes 15y agoNice.. looking forward to the meetup. In the meantime, if anyone wants tips/tricks or just to chat about it, feel free to contact me (email in my profile). I captured the flag late last last week. FWIW, Stripe has a campfire room setup for this as well - http://stripe.com/campfire http://stripe.com/campfire.
- gdb 15y agoThe CTF-specific room we set up is at: https://stripechat.campfirenow.com/59127 https://stripechat.campfirenow.com/59127
- why-el 15y agoWill the challenge continue on after you guys post the solutions? I have not had enough free time to have a go at it and would like to.
- gdb 15y agoWe're taking it down on Wednesday at noon PST. We'll probably bring it back sometime in the future though!
- mrchess 15y agoYou guys should stream this meetup so us east-coasters can watch too.
- jblock 15y agoDammit. It starts not 5 hours after I leave SV for Chicago :(