The Script.prototype.freeze/thaw functionality in Mozilla 1.4 and earlier allows attackers to execute native methods by modifying the string used as input to the script.thaw JavaScript function, which is then deserialized and executed.
SCO Internet Manager (mana) allows local users to execute arbitrary programs by setting the REMOTE_ADDR environment variable to cause menu.mana to run as if it were called from ncsa_httpd, then modifying the PATH environment variable to point to a malicious "hostname" program.
Vulnerability in xserver in SCO UnixWare 2.1.x and OpenServer 5.05 and earlier allows an attacker to cause a denial of service which prevents access to reserved port numbers below 1024.