XOR

Challenge

This string has been encrypted using XOR!

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message = " $6<&1#><*\x1a!$2\x22\x1a,\x1a- $7!\x1a<*0\x1a),. !\x1a=*78"

Solution

We perform all possible decryptions given that this is a simple XOR encryption and see if we get anything resembling a flag.

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ct = " $6<&1#><*\x1a!$2\x22\x1a,\x1a- $7!\x1a<*0\x1a),. !\x1a=*78"

for x in range (0,255):
    pt = ''
    for c in ct:
        pt += chr(ord(c) ^ x );
    print pt+" (x="+str(x)+")"

In this snippet of the output we see that when every character was XORed with value 69, we got the flag:

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[..]
d`rxbugzxn^e`vf^h^id`se^xnt^mhjde^yns| (x=68)
easyctf{yo_dawg_i_heard_you_liked_xor} (x=69)
fbpz`wexzl\gbtd\j\kfbqg\zlv\ojhfg\{lq~ (x=70)
gcq{avdy{m]fcue]k]jgcpf]{mw]nkigf]zmp (x=71)
[..]

Flag