As this affects all current users of Ubuntu who must use a proxy, I would recommend a Canonical-side workaround: configure the Squid servers supporting keyserver.ubuntu.com to serve requests when no Host: header is provided.
Currently, keyserver.ubuntu.com returns a 400 Bad Request when no Host: header is provided.
This bug is actually with GnuPG; I have reported it here:
https:/ /bugs.g10code. com/gnupg/ issue1799
As this affects all current users of Ubuntu who must use a proxy, I would recommend a Canonical-side workaround: configure the Squid servers supporting keyserver. ubuntu. com to serve requests when no Host: header is provided.
Currently, keyserver. ubuntu. com returns a 400 Bad Request when no Host: header is provided.