Advanced URL Filtering
URL Filtering Use Cases
Table of Contents
URL Filtering Use Cases
Discover ways you can use URL filtering to reduce your attack surface and ensure safe
web access.
Where can I use this? | What do I need? |
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Notes:
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There are many ways to enforce web page access beyond simply blocking and allowing
certain sites. For example, you can use multiple categories per URL to allow users to
access a site but block particular functions like submitting corporate credentials or
downloading files. You can also use URL categories to enforce different types of policy, such as Authentication,
Decryption, QoS, and Security.
Read on to learn about the different ways you can deploy URL filtering.
Control Web Access Based on URL category
You can create a URL Filtering profile
that specifies an action for a URL category and attach the profile to a Security
policy rule. The firewall enforces policy against traffic based on the settings in
the profile. For example, to block all gaming websites you would configure the block
action for the games category in a URL Filtering profile. After, you’d
attach the profile to Security policy rules that allow web access.
Multi-Category URL Filtering
Every URL can have up to four categories, including a risk category that indicates how likely a
site is to expose you to threats. More granular URL categorizations lets you move
beyond a basic “block-or-allow” approach to web access. For example, you can control
how users interact with content that is necessary for business but also more likely
to be used in a cyberattack.
You might consider certain URL categories risky but hesitate to block them outright because they
provide valuable resources (such as cloud storage services or blogs). Multi-category
URL filtering lets you allow users to visit sites that fall into these categories
while decrypting, inspecting, and enforcing read-only access to site content.
Additionally, you can define a custom URL category by selecting
the Category Match type and specifying two or more PAN-DB
categories. Creating a custom category from multiple categories allows you to target
enforcement for a website or page that matches all of the categories specified in
the custom URL category object.
Block or Allow Corporate Credential Submissions Based on URL Category
Prevent credential phishing by
enabling the firewall to detect corporate credential submissions to sites, and then
control those submissions based on URL category. Block users from submitting
credentials to malicious and untrusted sites, warn users against entering corporate
credentials on unknown sites or reusing corporate credentials on non-corporate
sites, and explicitly allow users to submit credentials to corporate and sanctioned
sites.
Enforce Safe Search Settings
Many search engines have a safe
search setting that filters out adult images and videos from search results. You can
enable the firewall to block search results or transparently enable safe search for
end users that are not using the strictest safe search settings. The firewall
supports safe search enforcement for the following search providers: Google, Yahoo,
Bing, Yandex, and YouTube. See how to get started with Safe Search Enforcement.
Enforce Password Access to Certain Sites
You can block access to a
site for most users while allowing certain users to access the site. See how to
allow password access to certain
sites.
Block High-Risk File Downloads from Certain URL Categories
You can block high-risk file downloads from specific URL categories by creating a Security policy
rule and attaching a File Blocking profile.
Enforce Security, Decryption, Authentication, and QoS Policy Rules Based on URL Category
You can enforce different types of policy rules based on URL categories. For example, suppose you
have enabled decryption, but want to exclude certain
personal information from being decrypted. In this case, you could create a
decryption policy rule that excludes websites that match the URL categories
financial-services and health-and-medicine from
decryption. Another example would be to use the URL category
streaming-media in a QoS policy rule to apply bandwidth controls to
websites in this category.
The following table describes the
policies that accept URL categories as match criteria:
Policy Type | Description |
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You can also use URL categories to phase-in
decryption, and to exclude URL categories that might contain
sensitive or personal information from decryption (like
financial-services and health-and-medicine). Plan to decrypt the riskiest traffic first (URL categories most likely to harbor malicious
traffic, such as high-risk) and then decrypt more as you gain
experience. Alternatively, decrypt the URL categories that don’t
affect your business first (if something goes wrong, it won’t
affect business), for example, news feeds. In both cases,
decrypt a few URL categories, listen to user feedback, run
reports to ensure that decryption is working as expected, and
then gradually decrypt a few more URL categories, and so on.
Plan to make decryption exclusions
for sites you can't decrypt either for technical reasons or
because you choose not to decrypt them. Decrypting traffic based on
URL categories is a best practice for both URL Filtering and
Decryption. | |
To ensure that users authenticate before being
allowed access to a specific category, you can attach a URL
category as a match criterion for Authentication policy
rules. | |
Use URL categories to allocate throughput levels
for specific website categories. For example, you may want to
allow the streaming-media category, but limit
throughput by adding the URL category to a QoS policy
rule. | |
You can use a URL category as match criteria or create a URL Filtering
profile that specifies an action for each category
and attach it to a Security policy rule.
Using URL Categories as Match Criteria vs. Applying URL
Filtering Profile to a Security Policy Rule
In a URL Filtering profile, the actions specified for each
URL category only apply to traffic destined for the
categories specified in the Security policy rule. You can
also apply a particular profile to multiple rules. If for example, the IT-security group in your company needs
access to the hacking category, but all other users
are denied access to the category, you must create the following
rules:
List the policy rule that allows access to hacking
before the policy rule that blocks hacking. This is
because the firewall evaluates Security policy rules from the
top down, so when a user who is part of the security group
attempts to access a hacking site, the firewall
evaluates the policy rule that allows access first and grants
the user access. The firewall evaluates users from all other
groups against the general web access rule that blocks access to
hacking sites.
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