Definition of tenc box seems invalid or too leniant

[rlaphoenix]

I've attached a sample tenc box from https://sho.com, specifically the show Yellowjackets S02E05 on the 2160p track.

It fails to parse with the following error:

Traceback (most recent call last):
  File "C:\Program Files\Python310\lib\runpy.py", line 196, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "C:\Program Files\Python310\lib\runpy.py", line 86, in _run_code
    exec(code, run_globals)
  File "C:\Program Files\Python310\Scripts\mp4dump.exe\__main__.py", line 7, in <module>
  File "C:\Users\User\AppData\Roaming\Python\Python310\site-packages\pymp4\cli.py", line 26, in dump
    box = Box.parse_stream(fd)
  File "C:\Users\User\AppData\Roaming\Python\Python310\site-packages\construct\core.py", line 186, in parse_stream
    return self._parse(stream, context, "parsing")
  File "C:\Users\User\AppData\Roaming\Python\Python310\site-packages\pymp4\parser.py", line 46, in _parse
    obj = self.subcon._parse(stream2, context, path)
  File "C:\Users\User\AppData\Roaming\Python\Python310\site-packages\construct\core.py", line 855, in _parse
    subobj = list(sc._parse(stream, context, path).items())
  File "C:\Users\User\AppData\Roaming\Python\Python310\site-packages\construct\core.py", line 297, in _parse
    return self.subcon._parse(stream, context, path)
  File "C:\Users\User\AppData\Roaming\Python\Python310\site-packages\construct\core.py", line 1544, in _parse
    obj = self.cases.get(key, self.default)._parse(stream, context, path)
  File "C:\Users\User\AppData\Roaming\Python\Python310\site-packages\construct\core.py", line 859, in _parse
    subobj = sc._parse(stream, context, path)
  File "C:\Users\User\AppData\Roaming\Python\Python310\site-packages\construct\core.py", line 2700, in _parse
    raise e.__class__("%s\n    %s" % (e, path))
construct.core.ConstError: expected 0 but parsed 25
    parsing -> _reserved1

It's failing at the byte 0xD with the value 0x19 (25 decimal). This offset would be the _reserved1 definition.

tenc_box_from_showtime_exact.zip