D-Bus 1.4.x through 1.6.x before 1.6.30, 1.8.x before 1.8.16, and 1.9.x before 1.9.10 does not validate the source of ActivationFailure signals, which allows local users to cause a denial of service (activation failure error returned) by leveraging a race condition involving sending an ActivationFailure signal before systemd responds.

D-Bus 1.3.0 through 1.6.x before 1.6.24 and 1.8.x before 1.8.8 does not properly close connections for processes that have terminated, which allows local users to cause a denial of service via a D-bus message containing a D-Bus connection file descriptor.

dbus 1.3.0 before 1.6.22 and 1.8.x before 1.8.6 allows local users to cause a denial of service (disconnect) via a certain sequence of crafted messages that cause the dbus-daemon to forward a message containing an invalid file descriptor.