Other articles

  1. TUM CTF: boot2brainfuck

    According to the description, hxp provides us with a brainfuck (BF) execution service where we can send BF programs over netcat and execute them. To help, they provide us with a script that translated BF programs into a DOS, 16-bit COM executable.

    Now as a reminder, DOS COM executables are …

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  2. Trend Micro CTF: base64 (crypto 500)

    Due to other commitments I only had little time to play during this CTF and when I arrived on Saturday (the 2nd day of the competition) our b01lers were already hacking away and we were hovering somewhere around 100.

    For quite a while I looked trough some of the others …

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  3. CSAW: sharpturn

    For this challenge we were given a corrupted git repository. We started by checking out the git repository (using git clone) and checking the consistency of the repository (using git fsck):

    Checking object directories: 100% (256/256), done.
    error: sha1 mismatch 354ebf392533dce06174f9c8c093036c138935f3
    error: 354ebf392533dce06174f9c8c093036c138935f3: object corrupt or missing
    error: sha1 …
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  4. 0CTF: treasure

    We are told that there's a treasure waiting at treasure.ctf.0ops.sjtu.cn so we have to start digging!

    Firing up dig: dig treasure.ctf.0ops.sjtu.cn -t ANY tells us that the target is a IPv6 address.

    Let's do a traceroute to that address:

    $ traceroute6 treasure.ctf …
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  5. 'sploits or having fun with the heap, stack, and format strings

    As part of the weekly CTF meetings we discussed some basic stack-based, heap-based, and format string based exploits. For system security challenges these are bread and butter techniques and rely on a huge amount of pre-existing knowledge about operating systems, kernels, process creation, dynamic loading, C programming, stack layouts, and …

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