Internet Explorer 7 to have tighter security zone settings
One of the changes Internet explorer 7.0 will see is a tightening of restrictions on the zone settings. Currently, there are four security zones for web sites: Internet, Intranet, Trusted Sites and Restricted Sites. Explorer tries to autodetect if a site is within the intranet (which becomes more trusted), or the internet (which becomes less trusted. The problem is this detection can be tricked and so, malicious websites can run in a less restrictive zone.
The fix for the problem is to NOT use the intranet zone unless the machine is part of a Windows Domain. One question I have is… does this mean that in a Windows domain environment, there’s still the possibility that a malicious site could masquerade as an intranet site? It sounds like that may be a chink in the armor. (How about not enabling intranet for ANY installs by default?) Though there is further detail that other zones will get locked down a bit tighter too…
Microsoft is also taking steps to lock down the Internet and Trusted Sites zones.
If a URL is in the Trusted Sites, it is given complete access, such as automatically installing ActiveX controls without permission. However, such capability has opened the zone up to abuse. For example, malware could automatically add a malicious site to the Trusted list. That will change in IE7.
In the future, Trusted Sites will be given a default security setting of Medium, the same level as the Internet zone in IE6. Users can manually change the security level back if they so please. “We find that many users don’t understand how powerful a site becomes when they make it a Trusted Site,” says Gupta.
The Internet zone in IE7 has been moved to a new Medium-High security setting. The change means ActiveX controls will be disabled by default, and users must enable them as needed through the yellow Information Bar. Windows Vista will go even further by running in a “Protected Mode” that runs IE in isolation.