Hack your way through Stripe's Capture the Flag

Re:Hack your way through Stripe's Capture the Flag by mpetrov on Friday February 24, 2012 @03:40AM (#3628481)

For level 06, I came up with a completely different solution. After hitting my head against the wall all day trying to fight with blocking/non-blocking IO, I resorted to a timing attack on the system call which worked really well. Check it out:

https://gist.github.com/1899389 (SPOILERS!)

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Re:Hack your way through Stripe's Capture the Flag by zx2c4 on Saturday February 25, 2012 @03:32AM (#3632538)

That's neat. Timing. Awesome.

I made mine a bit more reliable and made a movie.

Source: http://pastebin.com/6M4cq8gB Video: http://www.youtube.com/watch?v=_q2wTd1jgUQ

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Re:Hack your way through Stripe's Capture the Flag by benmmurphy on Saturday February 25, 2012 @09:57AM (#3633044)

i did it a different way to both of you but similar to zx2c4 's :) i found a way to block the child process from writing to stderr. i thought the way they were writing to stderr/ stdout was too much of a coincidence. all stdout writes end with \n

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Re:Hack your way through Stripe's Capture the Flag by zx2c4 on Saturday February 25, 2012 @04:12PM (#3633870)

Wadja end up doin'? Source?

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Re:Hack your way through Stripe's Capture the Flag by benmmurphy on Sunday February 26, 2012 @02:52AM (#3635108)

https://gist.github.com/1914845

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Re:Hack your way through Stripe's Capture the Flag by vd83 on Sunday February 26, 2012 @06:07PM (#3637112)

I had the same solution, just different heuristics..

http://pastebin.com/VfdmgwSA

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