Recently Updated
Dec 23
Challenge
Solution
We connect to the service using
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$ nc
nc challenges.hackvent.hacking-lab.com 8888
Riddle me this, riddle me that. What about solving a bunch of riddles for a present or two?
0, 1, 1, 2, 3 ... ?
Looks like the fibonacci sequence, let’s see what happens if we answer
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5
ACK, go ahead...
8
ACK, go ahead...
13
ACK, go ahead...
14
RST. Go ask Leonardo for help ...
Ok, seems like we need to keep going with the fibonacci sequence. We automate it using python:
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import telnetlib
# generator to produce fibonacci numbers
a,b = 0,1
def fibI():
global a,b
while True:
a,b = b, a+b
yield a
server = "challenges.hackvent.hacking-lab.com"
port = 8888
# get generator to the right point in the sequence
fib=fibI()
fib.next()
fib.next()
fib.next()
fib.next()
print "starting"
#connect to service
tn = telnetlib.Telnet(server, port)
print tn.read_until("\n")
print tn.read_until("\n")
# play until we win
response="ACK, go ahead..."
while response == "ACK, go ahead...":
# answer with next in fibonacci sequence
answer=fib.next()
print 'answering: '+str(answer)
tn.write(str(answer))
tn.write('\n')
response=tn.read_until('\n').strip('\n')
print response
# see what else they have to say
print tn.read_all()
This results in the following exchange:
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starting
Riddle me this, riddle me that. What about solving a bunch of riddles for a present or two?
0, 1, 1, 2, 3 ... ?
answering: 5
ACK, go ahead...
answering: 8
ACK, go ahead...
answering: 13
ACK, go ahead...
answering: 21
ACK, go ahead...
answering: 34
ACK, go ahead...
answering: 55
ACK, go ahead...
answering: 89
ACK, go ahead...
answering: 144
ACK, go ahead...
answering: 233
ACK, go ahead...
answering: 377
ACK, go ahead...
answering: 610
You really thought I would give away my precious stuff?
That was a joke. HAHA. FAT CHANCE.
(if you want to prank your friends, find this little code at http://hackvent.hacking-lab.com/KJYzeUErl7_riddler.tar.gz)
Ok, this was to easy to be the real challenge, but we did get the source code
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