The tag is present in Lintian version 2.104.328. That is the most recent version we know about.
The package contains D-Bus policy configuration that uses
one of the
send_* conditions, but does not specify a
send_destination, and is not specific to root.
Rules of the form
allow messages with the given interface to be sent to any service, not just the one installing the rule, which is rarely what was intended.
Similarly, on the system bus, rules of the form
are redundant with the system bus's default-deny policy, and have unintended effects on other services.
This check ignores rules of the form
<policy user="root"> <allow ... /> </policy>
which are commonly used for the "agent" pattern seen in services like
BlueZ and NetworkManager: a root-privileged daemon calls out to
one or more per-user user interface agent processes with no specific
send_destination is not easily applicable.
However, such rules should still be made as specific as possible to
avoid undesired side-effects.
Please refer to https://bugs.freedesktop.org/show_bug.cgi?id=18961 and http://lists.freedesktop.org/archives/dbus/2008-February/009401.html for details.