[issue9965] Loading malicious pickle may cause excessive memory usage

[Antoine Pitrou]

Antoine Pitrou <pitrou at free.fr> added the comment:

As an example of malicious pickle causing "excessive" memory usage, you can simply write:

>>> s = b'\x80\x03cbuiltins\nbytearray\nq\x00J\x00\x00\x00\x7f\x85q\x01Rq\x02.'
>>> _ = pickle.loads(s)

This will allocate an almost 2GB bytearray. You can of course change the size as you like. Here is the disassembly:

>>> pickletools.dis(s)
    0: \x80 PROTO      3
    2: c    GLOBAL     'builtins bytearray'
   22: q    BINPUT     0
   24: J    BININT     2130706432
   29: \x85 TUPLE1
   30: q    BINPUT     1
   32: R    REDUCE
   33: q    BINPUT     2
   35: .    STOP
highest protocol among opcodes = 2


Therefore, I would recommend closing this issue.

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<http://bugs.python.org/issue9965>
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