Telnet allows a remote client to specify environment variables including LD_LIBRARY_PATH, allowing an attacker to bypass the normal system libraries and gain root access.
SunOS sendmail 5.59 through 5.65 uses popen to process a forwarding host argument, which allows local users to gain root privileges by modifying the IFS (Internal Field Separator) variable and passing crafted values to the -oR option.
In Sendmail, attackers can gain root privileges via SMTP by specifying an improper "mail from" address and an invalid "rcpt to" address that would cause the mail to bounce to a program.
rmmount in SunOS 5.7 may mount file systems without the nosuid flag set, contrary to the documentation and its use in previous versions of SunOS, which could allow local users with physical access to gain root privileges by mounting a floppy or CD-ROM that contains a setuid program and running volcheck, when the file systems do not have the nosuid option specified in rmmount.conf.