By default, Internet Explorer 5.0 and other versions enables the "Navigate sub-frames across different domains" option, which allows frame spoofing.
Internet Explorer 3.x to 4.01 allows a remote attacker to insert malicious content into a frame of another web site, aka frame spoofing.
A remote attacker can read information from a Netscape user's cache via JavaScript.
JavaScript in Internet Explorer 3.x and 4.x, and Netscape 2.x, 3.x and 4.x, allows remote attackers to monitor a user's web activities, aka the Bell Labs vulnerability.
Netscape Communicator before version 4.73 and Navigator 4.07 do not properly validate SSL certificates, which allows remote attackers to steal information by redirecting traffic from a legitimate web server to their own malicious server, aka the "Acros-Suencksen SSL" vulnerability.