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import unittest
from unittest.mock import Mock
from nbxmpp import dispatcher
class XMLVulnerability(unittest.TestCase):
def setUp(self):
self.stream = Mock()
self.stream.is_websocket = False
self.dispatcher = dispatcher.StanzaDispatcher(self.stream)
self._error_handler = Mock()
self.dispatcher.subscribe('parsing-error', self._error_handler)
self.dispatcher.reset_parser()
def test_exponential_entity_expansion(self):
bomb = """<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE bomb [
<!ENTITY a "test">
<!ENTITY b "&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;&a;">
<!ENTITY c "&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;">
]>
<bomb>&c;</bomb>"""
self.dispatcher.process_data(bomb)
self._error_handler.assert_called()
def test_quadratic_blowup(self):
bomb = """<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE bomb [
<!ENTITY a "xxxxxxx... a couple of ten thousand chars">
]>
<bomb>&a;&a;&a;... repeat</bomb>"""
self.dispatcher.process_data(bomb)
self._error_handler.assert_called()
def test_external_entity_expansion(self):
bomb = """<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE external [
<!ENTITY ee SYSTEM "http://www.python.org/some.xml">
]>
<root>ⅇ</root>"""
self.dispatcher.process_data(bomb)
self._error_handler.assert_called()
def test_external_local_entity_expansion(self):
bomb = """<?xml version="1.0" encoding="utf-8"?>
<stream:stream xmlns:stream='http://etherx.jabber.org/streams' xmlns='jabber:client'>
<!DOCTYPE external [
<!ENTITY ee SYSTEM "file:///PATH/TO/simple.xml">
]>
<root>ⅇ</root>"""
self.dispatcher.process_data(bomb)
self._error_handler.assert_called()
def test_dtd_retrival(self):
bomb = """<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head/>
<body>text</body>
</html>"""
self.dispatcher.process_data(bomb)
self._error_handler.assert_called()
if __name__ == '__main__':
unittest.main()
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