A use-after-free flaw was found in D-Bus Development branch <= 1.13.16 dbus-1.12.x stable branch <= 1.12.18 and dbus-1.10.x and older branches <= 1.10.30 when a system has multiple usernames sharing the same UID. When a set of policy rules references these usernames D-Bus may free some memory in the heap which is still used by data structures necessary for the other usernames sharing the UID possibly leading to a crash or other undefined behaviors