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You can use security zones to
easily provide the appropriate level of security for the
various types of Web content that your users are likely to
encounter. For example, because you can fully trust sites
on your company's intranet, you probably want users to be
able to run all types of active content from this
location. To provide this capability, set the Local
intranet zone to a low level of security. You might not
feel as confident about sites on the Internet, so you can
assign a higher level of security to the entire Internet
zone. This higher level prevents users from running active
content and downloading code to their computers. However,
if there are specific sites you trust, you can place
individual URLs or entire domains in the Trusted sites
zone. For other sites on the Internet that are known to be
sources of potentially harmful Web content, you can select
the highest restrictions.
You can accept the default
security settings for each zone, or you can configure the
settings based on the needs of your organization and its
users. The options for configuring security zones are the
same whether you gain access to them from Internet
Explorer 6, the Internet Explorer Customization Wizard, or
the Internet
Explorer Administration Kit 6(IEAK) Profile Manager.
Note: When you upgrade to
Internet Explorer 6, Setup maintains the existing security
zone settings from previous browser versions, with one
exception-scripting is disabled in the Restricted sites
zone, regardless of your existing settings. Also, because
the default settings have changed for some options, your
existing settings may move to a custom level of security
in Internet Explorer 6.
Configuring
Security Zones
You can configure security zones
by using the following methods:
- In Internet Explorer, you can
use the Security tab.
- You can use the Internet
Explorer Customization Wizard to create custom browser
packages that include security zone settings for your
user groups. You can also lock down these settings to
prevent users from changing them.
- After the browser is deployed,
you can use the IEAK Profile Manager to manage
security zone settings through the automatic browser
configuration feature of Internet Explorer. You can
automatically push the updated security zone settings
to each user's desktop computer, enabling you to
manage security policy dynamically across all
computers on the network.
The options for configuring
security zones are the same whether you access them from
Internet Explorer 6, the Internet Explorer Customization
Wizard, or the IEAK Profile Manager. The following
procedure describes how to configure security zone
settings in the browser.
To configure security zone
settings
- On the Tools menu, click
Internet Options, and then click the Security
tab.
- Click a security zone to select
it and view its current settings.
- As necessary, change the
following settings:
- Security level. To
change the security level for the selected zone to
High, Medium, Medium-low, or Low,
move the slider. The on-screen description for
each level can help you decide which level to
select.
- Sites. To add or
remove Web sites from the zone, click the Sites
button, and then click the Add or Remove
button to customize your list of sites for the
selected zone.
- Custom level. For
more precise control of your security settings,
click the Custom Level button, and then select the
options you want. At any time, you can click
Default Level on the Security tab to return to the
original security level for the selected zone.
The process required for setting
up each security zone is described in the following
sections.
Setting
Up the Internet Zone
The Internet zone consists of all
Web sites that are not included in the other zones. By
default, the Internet zone is set to the Medium security
level. If you are concerned about possible security
problems when users browse the Internet, you might want to
change the security level to High. If you raise the
security level, Internet Explorer prevents some Web pages
from performing certain potentially harmful operations. As
a result, some pages might not function or be displayed
properly. Rather than use the High security level, you
might want to choose the Custom level so that you can
control each individual security decision for the zone.
Note: You cannot add Web
sites to the Internet zone.
Setting
Up the Local Intranet
Zone
To ensure a secure environment,
you must set up the Local intranet zone in conjunction
with your proxy servers and firewall. All sites in this
zone should be inside the firewall, and the proxy servers
should be configured so that an external Domain Name
System (DNS) name cannot be resolved to this zone.
Configuring the Local intranet zone requires that you have
a detailed knowledge of your existing networks, proxy
servers, and firewalls. For more information, see the MSDN
Online Web site.
By default, the Local intranet
zone consists of local domain names in addition to any
domains that are specified to bypass the proxy server. You
should confirm that these settings are secure for your
organization and adjust the settings as necessary. When
you set up the zone, you can specify the URL categories in
addition to specific sites in the zone.
To set up sites in the Local
intranet zone
- On the Tools menu, click
Internet Options, and then click the Security
tab.
- Click the Local intranet
zone.
- Click Sites, and then
select the following check boxes that apply:
- Include all local
(intranet) sites not listed in other zones.
Intranet sites, such as http://local, have names
that do not include dots. In contrast, a site name
that does contain dots, such as
http://www.microsoft.com, is not local. This site
would be assigned to the Internet zone. The
intranet site name rule applies to File URLs as
well as HTTP URLs.
- Include all sites that
bypass the proxy server. Typical intranet
configurations use a proxy server to gain access
to the Internet but have a direct connection to
intranet servers. The setting uses this kind of
configuration information to distinguish intranet
from Internet content. If your proxy server is
configured otherwise, you should clear this check
box and then use other means to designate the
Local intranet zone membership. For systems
without a proxy server, this setting has no
effect.
- Include all network
paths (UNCs). Network paths (for example,
\\servername\sharename\file.txt) are typically
used for local network content that should be
included in the Local intranet zone. If some of
your network paths should not be in the Local
intranet zone, clear this check box and then use
other means to designate the Local intranet zone
membership. In certain Common Internet File System
(CIFS) configurations, for example, it is possible
for a network path to reference Internet content.
- Click Advanced.
- Type the address of the site
you want to include in this zone, and then click Add.
- To require that server
verification be used, select the Require server
verification (https:) for all sites in this zone
check box.
The Local intranet zone is
intended to be configured by using the Internet Explorer
Customization Wizard or the IEAK Profile Manager, although
you can also find Local intranet options on the Security
tab, as described in the previous procedure. After the
Local intranet zone is confirmed to be secure, consider
changing the zone's security level to Low so that users
can perform a wider range of operations. You can also
adjust individual security settings by using the Custom
level of security for this zone. If parts of your intranet
are less secure or otherwise not trustworthy, you can
exclude the sites from this zone by assigning them to the
Restricted sites zone.
Setting
Up the Trusted and Restricted Sites Zones
You can add trusted and untrusted
Web sites to the Trusted sites and Restricted sites
security zones. These two zones enable you to assign
specific sites that you trust more or less than those in
the Internet zone or the Local intranet zone. By default,
the Trusted sites zone is assigned the Low security level.
This zone is intended for highly trusted sites, such as
the sites of trusted business partners.
If you assign a site to the
Trusted sites zone, the site will be allowed to perform a
wider range of operations. Also, Internet Explorer will
prompt you to make fewer security decisions. You should
add a site to this zone only if you trust all of its
content never to perform any harmful operations on your
computer. For the Trusted sites zone, Microsoft strongly
recommends that you use the Hypertext Transmission
Protocol, Secure (HTTPS) protocol or otherwise ensure that
connections to the site are completely secure.
By default, the Restricted sites
zone is assigned the High security level. If you assign a
site to the Restricted sites zone, it will be allowed to
perform only minimal, very safe operations. This zone is
for sites that you do not trust. Because of the need to
ensure a high level of security for content that is not
trusted, pages assigned to this zone might not function or
be displayed properly. When you install Internet Explorer
6 or upgrade to this browser version, the Restricted sites
zone disables active scripting and Java applets.
A content author can create a
frame or IFRAME with the "security=restricted"
attribute. This attribute puts the contents of the frame
or IFRAME, as well as any child frames (initiated by
parent frames) that it might contain, in the Restricted
sites zone. For example, if the http://a.com/ Web page
contains
<iframe
security=restricted
src="http://b.com/"></iframe>
and the http://b.com/ Web page
contains
<iframe
src="http://www.microsoft.com/></iframe>
both http://b.com/ and
http://www.microsoft.com/ will run in the Restricted sites
zone. The frame cannot run scripting or ActiveX controls,
unless the user changes the default settings for the
Restricted sites zone or you used the Internet Explorer
Customization Wizard to override the Restricted sites zone
settings for the Internet Explorer installation. Also,
this attribute blocks meta-refreshes (a mechanism that
allows a Web page to redirect to another Web page on a
timer without using script) within the frame or IFRAME.
Working
with Domain Name Suffixes
You can address Web content by
using either the DNS name or the Internet Protocol (IP)
address. You should assign sites that use both types of
addresses to the same zone. In some cases, the sites in
the Local intranet zone are identifiable either by their
local names or by IP addresses in the proxy bypass list.
However, if you enter the DNS name but not the IP address
for a site in the Trusted sites or Restricted sites zone
and the site is accessed by using the IP address, that
site might be treated as part of the Internet zone.
If you want to reference a Web
server by using a shorter version of its address that does
not include the domain, you can use a domain name suffix.
For example, you can reference a Web server named
sample.microsoft.com as sample. Then you can use either
http://sample.microsoft.com or http://sample to view that
content.
To set up this capability, you
must add the domain name suffix for TCP/IP properties to
the domain suffix search order.
To add the domain name suffix for
TCP/IP properties to the domain suffix search order in
Microsoft® Windows XP®
and Windows® 2000
- In Microsoft Windows XP or
Windows 2000, right-click the My Network Places
icon, and then click Properties.
- Right-click the appropriate
network connection, and then click Properties.
- On the General tab (for
a local area connection) or the Networking tab (for
all other connections), click Internet Protocol
(TCP/IP), and then click Properties.
- Click Obtain DNS server
address automatically if it is not already
selected.
- Click Advanced, and then
click the DNS tab.
- Click Append these DNS
suffixes (in order), and then click Add.
- Type the domain suffix, and
then click Add.
To add the domain name suffix for
TCP/IP properties to the domain suffix search order in
Windows 98
- In Microsoft®
Windows 98®, right-click the Network
Neighborhood desktop icon, and then click Properties.
- On the Configuration
tab, click TCP/IP, and then click Properties.
- Click the DNS Configuration
tab, and then select Enable DNS if it is not
already selected.
- In the Domain Suffix Search
Order box, add the search order that you want.
It is important to set up security
zones correctly for this capability. By default, the URL
without dots (http://sample) is considered to be in the
Local intranet zone, and the URL with dots
(http://sample.microsoft.com) is considered to be in the
Internet zone. Therefore, if you use this capability and
no proxy server bypass is available to clearly assign the
content to the proper zone, you need to change the zone
settings.
Depending on whether the content
accessed by the domain name suffix is considered intranet
or Internet content, you need to assign the ambiguous site
URLs to the appropriate zones. To assign URLs, such as
http://sample, to the Internet zone, clear the Include
all local (intranet) sites not listed in other zones
check box for the Local intranet zone, and include the
site in the Internet zone.
Selecting
Custom Level Settings
The Custom Level button on
the Security tab gives you additional control over
zone security. You can enable or disable specific security
options depending on the needs of your organization and
its users.
The Custom level security options
for Internet Explorer are grouped into the following
categories:
- Microsoft®
ActiveX® controls and plug-ins
- Downloads
- Microsoft VM
- Miscellaneous
- Scripting
- User Authentication
Note: If you upgrade from
Internet Explorer 5.5 or an earlier browser version,
Internet Explorer 6 maintains your existing Custom level
security settings.
The following tables identify the
default value for each Custom level security option at
each security level.
ActiveX
Controls and Plug-Ins
The following options dictate how
Internet Explorer approves, downloads, runs, and scripts
ActiveX controls and plug-ins.
Note:
- If a user downloads an ActiveX
control from a site that is different from the page on
which it is used, Internet Explorer applies the more
restrictive of the two sites' zone settings. For
example, if a user views a Web page within a zone that
is set to permit a download, but the code is
downloaded from another zone that is set to prompt a
user first, Internet Explorer uses the prompt setting.
- Download signed ActiveX
controls. This option determines whether users can
download signed ActiveX controls from a page in the
zone. This option has the following settings:
- Disable, which prevents all
signed controls from downloading.
- Enable, which downloads
valid signed controls without user intervention
and prompts users to choose whether to download
invalid signed controls—that is, controls that
have been revoked or have expired.
- Prompt, which prompts users
to choose whether to download controls signed by
publishers who are not trusted, but still silently
downloads code validly signed by trusted
publishers.
- Download unsigned ActiveX
controls. This option determines whether users can
download unsigned ActiveX controls from the zone. This
code is potentially harmful, especially when it comes
from an untrusted zone. This option has the following
settings:
- Disable, which
prevents unsigned controls from running.
- Enable, which runs
unsigned controls without user intervention.
- Prompt, which
prompts users to choose whether to allow the
unsigned control to run.
- Initialize and script
ActiveX controls not marked as safe. ActiveX
controls are classified as either trusted or
untrusted. This option controls whether a script can
interact with untrusted controls in the zone.
Untrusted controls are not meant for use on Internet
pages, but in some cases they can be used with pages
that can be absolutely trusted not to use the controls
harmfully. Object safety should be enforced unless you
can trust all ActiveX controls and scripts on pages in
the zone. This option has the following settings:
- Disable, which
enforces object safety for untrusted data or
scripts. ActiveX controls that cannot be trusted
are not loaded with parameters or scripted.
- Enable, which
overrides object safety. ActiveX controls are run,
loaded with parameters, and scripted without
setting object safety for untrusted data or
scripts. This setting is not recommended, except
for secure and administered zones. This setting
causes Internet Explorer to initialize and script
both untrusted and trusted controls and ignore the
Script ActiveX controls marked safe for
scripting option.
- Prompt, which
attempts to enforce object safety. However, if
ActiveX controls cannot be made safe for untrusted
data or scripts, users are given the option of
allowing the control to be loaded with parameters
or to be scripted.
For more information about how to
make ActiveX controls safe, see the MSDN
Online Web site.
- Run ActiveX controls and
plug-ins. This option determines whether Internet
Explorer can run ActiveX controls and plug-ins from
pages in the zone. This option has the following
settings:
- Administrator approved,
which runs only those controls and plug-ins that
you have approved for your users. To select the
list of approved controls and plug-ins, use
Internet Explorer system policies and
restrictions. The Control Management category of
policies enables you to manage these controls.
- Disable, which
prevents controls and plug-ins from running.
- Enable, which runs
controls and plug-ins without user intervention.
- Prompt, which
prompts users to choose whether to allow the
controls or plug-ins to run.
- Script ActiveX controls
marked safe for scripting. This option determines
whether an ActiveX control that is marked safe for
scripting can interact with a script. This option does
not affect controls that are loaded with <param>
tags. This option has the following settings:
- Disable, which
prevents script interaction. Disabling ActiveX
control scripting will also prevent applets from
being scripted.
- Enable, which allows
script interaction without user intervention.
- Prompt, which
prompts users to choose whether to allow script
interaction.
Internet Explorer ignores this
option when Initialize and script ActiveX controls that
are not marked safe is set to Enable, because
that setting bypasses all object safety. You cannot script
unsafe controls while blocking the scripting of the safe
ones.
Note: In Internet Explorer
5 and earlier versions of the browser, this option was
enabled for all security levels. If you upgrade to
Internet Explorer 6 and you did not disable this option in
your previous browser version, it will remain enabled in
Internet Explorer 6.
ActiveX Controls and Plug-Ins
| Download
signed ActiveX controls |
Enable |
Prompt |
Prompt |
Disable |
| Download
unsigned ActiveX controls |
Prompt |
Disable |
Disable |
Disable |
| Initialize
and script ActiveX controls not marked as safe |
Prompt |
Disable |
Disable |
Disable |
| Run
ActiveX controls and plug-ins |
Enable |
Enable |
Enable |
Disable |
| Script
ActiveX controls marked safe for scripting |
Enable |
Enable |
Enable |
Disable |
Downloads
Download options specify how
Internet Explorer handles downloads as follows:
- File download. This
option controls whether file downloads are permitted
based on the zone of the Web page that contains the
download link, not the zone from which the file
originated. This option has the following settings:
- Disable, which
prevents files from being downloaded from the
zone.
- Enable, which allows
files to be downloaded from the zone.
- Font download. This
option determines whether Web pages within the zone
can download HTML fonts. This option has the following
settings:
- Disable, which
prevents HTML fonts from being downloaded.
- Enable, which
downloads HTML fonts without user intervention.
- Prompt, which
prompts users to choose whether to allow the
download of HTML fonts.
Downloads
| File
download |
Enable |
Enable |
Enable |
Disable |
| Font
download |
Enable |
Enable |
Enable |
Prompt |
Miscellaneous
Options
These options control whether
users can access data sources across domains, submit
nonencrypted form data, launch applications and files from
IFRAME elements, install desktop items, drag and drop
files, copy and paste files, and access software channel
features from this zone.
- Access data sources across
domains. This option specifies whether components
that connect to data sources should be allowed to
connect to a different server to obtain data. This
option has the following settings:
- Disable, which
allows database access only in the same domain as
the Web page.
- Enable, which allows
database access to any source, including other
domains.
- Prompt, which
prompts users before allowing database access to
any source in other domains.
- Allow META REFRESH. This
option specifies whether Web pages can use
meta-refreshes to reload pages after a preset delay.
This option has the following settings:
- Disable, which
prevents Web pages from using meta-refreshes.
- Enable, which allows
Web pages to use meta-refreshes.
- Display mixed content.
This option specifies whether Web pages can display
content from both secure and non-secure servers. This
option has the following settings:
- Disable, which
prevents Web pages from displaying non-secure
content.
- Enable, which allows
Web pages to display both secure and non-secure
content.
- Prompt, which
prompts users before allowing Web pages to display
both secure and non-secure content.
- Don't prompt for client
certificate selection when no certificates or only one
certificate exists. This option specifies whether
users are prompted to select a certificate when no
trusted certificate or only one trusted certificate
has been installed on the computer. This option has
the following settings:
- Disable, which
allows users to be prompted for a certificate.
- Enable, which
prevents users from being prompted for a
certificate.
- Drag and drop or copy and
paste files. This option controls whether users
can drag and drop, or copy and paste, files from Web
pages within the zone. This option has the following
settings:
- Disable, which
prevents users from dragging and dropping files,
or copying and pasting files, from the zone.
- Enable, which
enables users to drag and drop files, or copy and
paste files, from the zone without being prompted.
- Prompt, which
prompts users to choose whether they can drag and
drop files, or copy and paste files, from the
zone.
- Installation of desktop
items. This option controls whether users can
install desktop items from Web pages within the zone.
This option has the following settings:
- Disable, which
prevents users from installing desktop items from
this zone.
- Enable, which
enables users to install desktop items from this
zone without being prompted.
- Prompt, which
prompts users to choose whether they can install
desktop items from this zone.
- Launching programs and files
in an IFRAME. This option controls whether users
can launch programs and files from an IFRAME element
(containing a directory or folder reference) in Web
pages within the zone. This option has the following
settings:
- Disable, which
prevents programs from running and files from
downloading from IFRAME elements on Web pages in
the zone.
- Enable, which runs
programs and downloads files from IFRAME elements
on Web pages in the zone without user
intervention.
- Prompt, which
prompts users to choose whether to run programs
and download files from IFRAME elements on Web
pages in the zone.
- Navigate sub-frames across
different domains. This option controls whether
readers of a Web page can navigate the sub-frame of a
window with a top-level document that resides in a
different domain. This option has the following
settings:
- Disable, which
allows users to navigate only between Web page
sub-frames that reside in the same domain.
- Enable, which allows
users to navigate between all Web page sub-frames,
regardless of the domain, without being prompted.
- Prompt, which
prompts users to choose whether to navigate
between Web page sub-frames that reside in
different domains.
- Software channel
permissions. This option controls the permissions
given to software distribution channels. This option
has the following settings:
- High safety, which
prevents users from being notified about software
updates by e-mail, software packages from being
automatically downloaded to users' computers, and
software packages from being automatically
installed on users' computers.
- Low safety, which
notifies users about software updates by e-mail,
allows software packages to be automatically
downloaded to users' computers, and allows
software packages to be automatically installed on
users' computers.
- Medium safety, which
notifies users about software updates by e-mail
and allows software packages to be automatically
downloaded to (but not installed on) users'
computers. The software packages must be validly
signed; users are not prompted about the download.
- Submit nonencrypted form
data. This option determines whether HTML pages in
the zone can submit forms to or accept forms from
servers in the zone. Forms sent with Secure Sockets
Layer (SSL) encryption are always allowed; this
setting only affects data that is submitted by non-SSL
forms. This option has the following settings:
- Disable, which
prevents information from forms on HTML pages in
the zone from being submitted.
- Enable, which allows
information from forms on HTML pages in the zone
to be submitted without user intervention.
- Prompt, which
prompts users to choose whether to allow
information from forms on HTML pages in the zone
to be submitted.
- Userdata persistence.
This option determines whether a Web page can save a
small file of personal information associated with the
page to the computer. This option has the following
settings:
- Disable, which
prevents a Web page from saving a small file of
personal information to the computer.
- Enable, which allows
a Web page to save a small file of personal
information to the computer.
Miscellaneous
| Access
data sources across domains |
Enable |
Prompt |
Disable |
Disable |
| Allow
META REFRESH |
Enable |
Enable |
Enable |
Disable |
| Display
mixed content |
Prompt |
Prompt |
Prompt |
Prompt |
| Don't
prompt for client certificate selection when
no certificates or only one certificate exists |
Enable |
Enable |
Disable |
Disable |
| Drag
and drop or copy and paste files |
Enable |
Enable |
Enable |
Prompt |
| Installation
of desktop items |
Enable |
Prompt |
Prompt |
Disable |
| Launching
programs and files in an IFRAME |
Enable |
Prompt |
Prompt |
Disable |
| Navigate
sub-frames across different domains |
Enable |
Enable |
Enable |
Disable |
| Software
channel permissions |
Low
safety |
Medium
safety |
Medium
safety |
High
safety |
| Submit
nonencrypted form data |
Enable |
Enable |
Prompt |
Prompt |
| Userdata
persistence |
Enable |
Enable |
Enable |
Disable |
 |
Scripting
Scripting options specify how
Internet Explorer handles scripts.
- Active scripting. This
option determines whether Internet Explorer can run
script code on Web pages in the zone. This option has
the following settings:
- Disable, which
prevents scripts from running.
- Enable, which runs
scripts without user intervention.
- Prompt, which
prompts users about whether to allow the scripts
to run.
- Allow paste operations via
script. This option determines whether a Web page
can cut, copy, and paste information from the
Clipboard. This option has the following settings:
- Disable, which
prevents a Web page from cutting, copying, and
pasting information from the Clipboard.
- Enable, which allows
a Web page to cut, copy, and paste information
from the Clipboard without user intervention.
- Prompt, which
prompts users about whether to allow a Web page to
cut, copy, or paste information from the
Clipboard.
- Scripting of Java applets.
This option determines whether scripts within the zone
can use objects that exist within Java applets. This
capability allows a script on a Web page to interact
with a Java applet. This option has the following
settings:
- Disable, which
prevents scripts from accessing applets.
- Enable, which allows
scripts to access applets without user
intervention.
- Prompt, which
prompts users about whether to allow scripts to
access applets.
Internet Explorer ignores this option when Script
ActiveX controls marked safe for scripting is set
to Disable. In this case, Scripting of Java
applets is also disabled.
Scripting
| Active
scripting |
Enable |
Enable |
Enable |
Disable |
| Allow
paste operations via script |
Enable |
Enable |
Enable |
Disable |
| Scripting
of Java applets |
Enable |
Enable |
Enable |
Disable |
 |
User
Authentication
The User Authentication option
controls how HTTP user authentication is handled.
- Logon. This option has
the following settings:
- Anonymous logon,
which disables HTTP authentication and uses the
guest account only for authentication using the
Common Internet File System (CIFS) protocol.
- Automatic logon only in
Intranet zone, which prompts users for user
IDs and passwords in other zones. After users are
prompted, these values can be used silently for
the remainder of the session.
- Automatic logon with
current username and password, which attempts
logon using Windows NT Challenge Response (also
known as NTLM authentication), an authentication
protocol between the client computer and the
application server. If Windows NT Challenge
Response is supported by the server, the logon
uses the network user name and password for logon.
If the server does not support Windows NT
Challenge Response, users are prompted to provide
their user names and passwords.
- Prompt for user name and
password, which prompts users for user IDs and
passwords. After users are prompted, these values can
be used silently for the remainder of the session.
User Authentication
| Logon |
Automatic
logon with current username and password |
Automatic
logon only in Intranet zone |
Automatic
logon only in Intranet zone |
Prompt
for user name and password |
These Custom level security
options apply to Internet Explorer; other programs might
not accept them. These security options are for Win64™
and Win32® versions of the
Microsoft® Windows®
operating system. The following sections describe these
settings in greater detail.
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