Off-by-one error in D-Bus 1.3.0 through 1.6.x before 1.6.24 and 1.8.x before 1.8.8, when running on a 64-bit system and the max_message_unix_fds limit is set to an odd number, allows local users to cause a denial of service (dbus-daemon crash) or possibly execute arbitrary code by sending one more file descriptor than the limit, which triggers a heap-based buffer overflow or an assertion failure.