ConnectionResetError when running --http_headers

[wondex]

Describe the bug

Traceback (most recent call last):
  File "/opt/rh/rh-python38/root/usr/local/lib/python3.8/site-packages/sslyze/scanner.py", line 264, in get_results
    result = implementation_cls.result_for_completed_scan_jobs(
  File "/opt/rh/rh-python38/root/usr/local/lib/python3.8/site-packages/sslyze/plugins/http_headers_plugin.py", line 165, in result_for_completed_scan_jobs
    return completed_scan_jobs[0].result()
  File "/opt/rh/rh-python38/root/usr/lib64/python3.8/concurrent/futures/_base.py", line 432, in result
    return self.__get_result()
  File "/opt/rh/rh-python38/root/usr/lib64/python3.8/concurrent/futures/_base.py", line 388, in __get_result
    raise self._exception
  File "/opt/rh/rh-python38/root/usr/lib64/python3.8/concurrent/futures/thread.py", line 57, in run
    result = self.fn(*self.args, **self.kwargs)
  File "/opt/rh/rh-python38/root/usr/local/lib/python3.8/site-packages/sslyze/plugins/http_headers_plugin.py", line 184, in _retrieve_and_analyze_http_response
    http_response = HttpResponseParser.parse_from_ssl_connection(ssl_connection.ssl_client)
  File "/opt/rh/rh-python38/root/usr/local/lib/python3.8/site-packages/sslyze/connection_helpers/http_response_parser.py", line 23, in parse_from_ssl_connection
    return cls._parse(ssl_conn.read)
  File "/opt/rh/rh-python38/root/usr/local/lib/python3.8/site-packages/sslyze/connection_helpers/http_response_parser.py", line 29, in _parse
    response = read_method(4096)
  File "/opt/rh/rh-python38/root/usr/local/lib64/python3.8/site-packages/nassl/ssl_client.py", line 223, in read
    encrypted_data = self._sock.recv(self._DEFAULT_BUFFER_SIZE)
ConnectionResetError: [Errno 104] Connection reset by peer

To Reproduce
Install SSLyze using: pip
Run the following command: /opt/rh/rh-python38/root/usr/bin/python3.8 -m sslyze --regular

Expected behavior
Successful scan

Python environment (please complete the following information):
OS: Red Hat Enterprise Linux Server release 7.9 (Maipo)
Python version: 3.8
SSLyzeL: 4.0.2

[nabla-c0d3]

@wondex Could you send me the server that triggered this issue? Otherwise I won't be able to fix it. Thanks!

[wondex]

Hi Alban,

This are internal hosts, but the behavior of this hosts are the same:
The are not sending any response headers.

Google Chrome browser:
Status = (failed) net::ERR_CONNECTION_RESET

Curl:

> GET / HTTP/1.1
> User-Agent: curl/7.29.0
> Host: <internal host>
> Accept: */*
>
* SSL read: errno -5961 (PR_CONNECT_RESET_ERROR)
* TCP connection reset by peer
* Closing connection 0
curl: (56) TCP connection reset by peer

[nabla-c0d3]

Fixed in v4.0.4.