D-Bus is a message bus system, a simple way for applications to talk to one another.
D-Bus doesn’t validate the source of ActivationFailure signals.
A local attacker could possibly cause a Denial of Service condition.
There is no known workaround at this time.
All D-Bus users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=sys-apps/dbus-1.8.16"