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Intercepting flows to mitm.it crashes mitmproxy

See original GitHub issue

Trying out mitmproxy. When I capture a connection and attempt to accept it mitmproxy crashes.

Steps to reproduce the problem:

Install mitmproxy from homebrew, trust the CA certificate, configure Chrome proxy settings.
Capture a flow/connection (in my case I navigated to mitm.it)
Accept the flow, mitmproxy will now crash.

Any other comments? What have you tried so far?

Traceback (most recent call last):
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/mitmproxy/tools/console/master.py", line 281, in run
    self.loop.run()
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/urwid/main_loop.py", line 278, in run
    self._run()
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/urwid/main_loop.py", line 376, in _run
    self.event_loop.run()
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/urwid/main_loop.py", line 682, in run
    self._loop()
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/urwid/main_loop.py", line 719, in _loop
    self._watch_files[fd]()
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/urwid/raw_display.py", line 393, in <lambda>
    event_loop, callback, self.get_available_raw_input())
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/urwid/raw_display.py", line 493, in parse_input
    callback(processed, processed_codes)
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/urwid/main_loop.py", line 403, in _update
    self.process_input(keys)
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/urwid/main_loop.py", line 503, in process_input
    k = self._topmost_widget.keypress(self.screen_size, k)
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/mitmproxy/tools/console/window.py", line 84, in keypress
    k = super().keypress(size, k)
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/urwid/container.py", line 1128, in keypress
    return self.body.keypress( (maxcol, remaining), key )
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/mitmproxy/tools/console/flowview.py", line 513, in keypress
    self.flow.resume()
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/mitmproxy/flow.py", line 179, in resume
    self.reply.ack()
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/mitmproxy/controller.py", line 155, in ack
    self.send(self.obj, force)
  File "/usr/local/Cellar/mitmproxy/2.0.2/libexec/lib/python3.6/site-packages/mitmproxy/controller.py", line 166, in send
    raise exceptions.ControlException("There is already a reply message.")
mitmproxy.exceptions.ControlException: There is already a reply message.

System information

Mitmproxy version: 2.0.2 (release version) Python version: 3.6.1 Platform: Darwin-15.6.0-x86_64-i386-64bit SSL version: OpenSSL 1.1.0f 25 May 2017 Mac version: 10.11.6 (‘’, ‘’, ‘’) x86_64

Issue Analytics

State:
Created 6 years ago
Comments:8 (4 by maintainers)

Top GitHub Comments

1reaction

jtl999commented, Feb 11, 2021

Am I missing something here or has this bug been resolved?

Appears to have been fixed since my last comment.

0reactions

alt-glitchcommented, Feb 11, 2021

Trying to reproduce this issue on Manjaro 20.2.1 but mimproxy seems to be intercepting mitm.it requests properly. Am I missing something here or has this bug been resolved? System Information Mitmproxy: 6.0.2 Python: 3.9.1 OpenSSL: OpenSSL 1.1.1i 8 Dec 2020 Platform: Linux-5.10.7-3-MANJARO-x86_64-with-glibc2.32

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