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PicoCTF2018 - Miscellaneous - Stings

PicoCTF2018 - Miscellaneous - Strings

Objectives

Can you find the flag in this file [1]  without actually running it? You can also find the file in /problems/strings_1_c7bac958dd6a4b695dc72446d8014f59 on the shell server.



Solutions

Connect up to the shell and cd to the appropriate folder



@pico-2018-shell:/$ cd /problems/strings_1_c7bac958dd6a4b695dc72446d8014f59                                 
@pico-2018-shell:/problems/strings_1_c7bac958dd6a4b695dc72446d8014f59$ ls                                   
strings


Let's run strings and see what it does

@pico-2018-shell:/problems/strings_1_c7bac958dd6a4b695dc72446d8014f59$ ./strings                               

Have you ever used the 'strings' function? Check out the man pages!

Okay let's check out the man like the hint says

man Strings
STRINGS(1)                                       GNU Development Tools                                       STRINGS(1) 
                                                                                                                       
NAME                                                                                                                   
       strings - print the strings of printable characters in files. 


If we strings ./strings

ok now its dumping a bunch of lines of text, the flag will most  likely be in this list

let's pipe it into grep and search for Pico

@pico-2018-shell:/problems/strings_1_c7bac958dd6a4b695dc72446d8014f59$ strings  ./strings | grep 'pico'     
picoCTF{sTrIngS_sAVeS_Time_d7c8de6c}                                                 

                                 
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