Operating systems with shared memory implementations based on BSD 4.4 code allow a user to conduct a denial of service and bypass memory limits (e.g., as specified with rlimits) using mmap or shmget to allocate memory and cause page faults.

A buffer overflow in lsof allows local users to obtain root privilege.

IP fragmentation denial of service in FreeBSD allows a remote attacker to cause a crash.

ICMP messages to broadcast addresses are allowed, allowing for a Smurf attack that can cause a denial of service.

The access permissions for a UNIX domain socket are ignored in Solaris 2.x and SunOS 4.x, and other BSD-based operating systems before 4.4, which could allow local users to connect to the socket and possibly disrupt or control the operations of the program using that socket.