rdist in various UNIX systems uses popen to execute sendmail, which allows local users to gain root privileges by modifying the IFS (Internal Field Separator) variable.

The "me" user in NeXT NeXTstep 2.1 and earlier has wheel group privileges, which could allow the me user to use the su command to become root.

Vulnerability in restore0.9 installation script in NeXT 1.0a and 1.0 allows local users to gain root privileges.

Vulnerability in NeXT 1.0a and 1.0 with publicly accessible printers allows local users to gain privileges via a combination of the npd program and weak directory permissions.

BuildDisk program on NeXT systems before 2.0 does not prompt users for the root password, which allows local users to gain root privileges.