The server (download) is a 32-bit non-stripped binary. When we connect to the server, we got three options:

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Welcome to the jungle library mate! Try to escape!!
 
 r - read from library
 a - add element
 u - exit

Let’s see what the first two options do:

This is my second time participating in DC qualifier, and it is really a fun experience.

This challenge (download) involves multiple steps. When we connect to the server, we need to play a game first.

Running the program shows a progress bar and gives a core dump:

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alpha@alpha-th:~/Copy/ctf/asis2015/re/100$ ./tera_85021482a68d6ed21892ea99b84f13f3
Please wait until my job be done 
%0.0000000 [                          Segmentation fault (core dumped)

Let’s look at the output from strace (other lines are omitted):

hi, I’m morgan.