• Universal dangerous positive: 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:


    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
    	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:

    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.