NetWare NFS mode 1 and 2 implements the "Read Only" flag in Unix by changing the ownership of a file to root, which allows local users to gain root privileges by creating a setuid program and setting it to "Read Only," which NetWare-NFS changes to a setuid root program.
Novell 5 and earlier, when running over IPX with a packet signature level less than 3, allows remote attackers to gain administrator privileges by spoofing the MAC address in IPC fragmented packets that make NetWare Core Protocol (NCP) calls.