Created attachment 425539 [details] Result from http/tests/media/reference.mov When not specifying the Content-Length header in http/tests/security/resources/reference-movie-cross-origin-allow.py, the test calling the file times out, but does pass when specifying the Content-Length. http/tests/media/resources/reference.mov is what is called by reference-movie-cross-origin-allow.py and its binary content is the body being sent (see attached). http/tests/media/resources/test.mp4 is called in the access_log when specifying the Content-Length header, but is not when omitted (test.mp4 is called from reference.mov). Use run-webkit-tests --root ./build/to/test http/tests/security/video-cross-origin-caching.html to run the file in question and see failure.