• Universal dangerous positive: 194.226.244.125:1024. Send me your password: "3k8bbz032mrap75c8iz8tmi7f4ou00". Flag format is "RUCTF_.*"

  • In this task we are given a cpp source file with many libraries used and without any includes, you can find source here. So, the problem is pretty clear - find all the libraries, install and incldue them correctly.

  • In this task we have two similar messages of the form x + “Alex” (we'll call it x1) and x + “Jane” (we'll call it x2) where “+” is concatenation. These messages are encrypted with the RSA cipher using the same key (the module and the public exponent are given). The resulting messages are also provided:

    61be5676e0f8311dce5d991e841d180c95b9fc15576f2ada0bc619cfb
    991cddfc51c4dcc5ecd150d7176c835449b5ad085abec38898be02d27
    49485b68378a8742544ebb8d6dc45b58fb9bac4950426e3383fa31a93
    3718447decc5545a7105dcdd381e82db6acb72f4e335e244242a8e0fb
    bb940edde3b9e1c329880803931c
    
    9d3c9fad495938176c7c4546e9ec0d4277344ac118dc21ba4205a3451
    e1a7e36ad3f8c2a566b940275cb630c66d95b1f97614c3b55af860949
    5fc7b2d732fb58a0efdf0756dc917d5eeefc7ca5b4806158ab87f4f44
    7139d1daf4845e18c8c7120392817314fec0f0c1f248eb31af153107b
    d9823797153e35cb7044b99f26b0
    

    The task is simple—find x.

  • Note: scroll down for the English translation.

    Взломайте TLS. 
    Формат флага — «RUCTF_.*»

  • In this task we were given a fragment of the server-side code:

    buf = c.recv(4096)
    digest, msg = buf.split(" ", 1)
    if (digest == md5(password+msg).hexdigest()):
    	#here I send a secret
    else:
    	c.send("Wrong signature\n")
    

    It is also known that this string passes the test: “b34c39b9e83f0e965cf392831b3d71b8 do test connection” Unfortunately, this message is filtered and won't work, so we need to create a new correct message.

  • 2 files are given:
    rtl_sdr_capture.bin
    SimspyTrace.log

    Task name hints us to start with searching information about capturing GSM traffic.
     Second link in google leads us to the great GSM write up written by Domi: http://domonkos.tomcsanyi.net/?p=418 [1]

  • Webpage with some historical information about CTF games in Russia is given.
    There is the first hint on the page: "Language was detect automatically :)"
    The second hint is the task name: php.
    Googling for localization in php puts an idea of php inclusion in my head.

  • Pcap file with bluetooth traffic captured was given.
    I tried to extract some data from it using ComProbe Protocol Analysis System (free to download). It has feature to extract data and audio from bluetooth with one click.
    I got two .wav files. The second one contains flag.

  • На семинаре было рассказано о структуре ELF файла и о том, что происходит до того как управление переходит к функции main.