.. _version_history_1.15.4:

1.15.4 (April 15, 2021)
========================



Changes
-------


* **http**: fixed URL parsing for HTTP/1.1 fully qualified URLs and connect requests containing IPv6 addresses.
* **http**: fixed a crash upon receiving empty HTTP/2 metadata frames. Received empty metadata frames are now counted in the HTTP/2 codec stat :ref:`metadata_empty_frames <v1.15:config_http_conn_man_stats_per_codec>`.
* **http**: fixed a remotely exploitable integer overflow via a very large grpc-timeout value causes undefined behavior.
* **http**: fixed bugs in datadog and squash filter's handling of responses with no bodies.
* **http**: reverting a behavioral change where upstream connect timeouts were temporarily treated differently from other connection failures. The change back to the original behavior can be temporarily reverted by setting ``envoy.reloadable_features.treat_upstream_connect_timeout_as_connect_failure`` to false.
* **tls**: fix detection of the upstream connection close event.