Advanced URL Filtering
Get Started with URL Filtering
Table of Contents
Get Started with URL Filtering
Basic setup for a URL filtering deployment that informs a more robust
configuration
Where can I use this? | What do I need? |
---|---|
|
Notes:
|
The first step to get started with URL filtering is understanding the web activity patterns of
users on your network.
To safely observe these patterns, we recommend the following:
- Review Palo Alto Networks predefined URL categories.
-
Enter URLs into our Test A Site engine to see how PAN-DB categorizes them.
-
Create a (mostly) passive URL Filtering profile that alerts on most categories. When you select the alert setting for a URL category, the firewall logs traffic to that category. Then, you can see the sites your users are accessing and decide on the appropriate site access for URL categories and specific sites.Alerting on all web activity might create a large number of log files. As a result, you might only want to do this as part of an initial deployment. At that time, you can also reduce URL filtering logs by enabling the Log container page only option in the URL Filtering profile so only the main page that matches the category will be logged, not subsequent pages or categories that may be loaded within the container page.
-
Block URL categories that we know are bad: malware, command-and-control, and phishing.
Get Started with Advanced URL Filtering (Strata Cloud Manager)
If you’re using Panorama to manage Prisma Access:
Toggle over to the PAN-OS & Panorama tab
and follow the guidance there.
If you’re using Strata Cloud Manager, continue here.
- Use Test A Site to check how PAN-DB categorizes a
specific website.You can also use the platform to request a categorization change for any website that you believe has been incorrectly categorized.
- Create a passive URL Access Management profile that alerts on all
categories.The firewall generates a URL filtering log entry for websites in URL categories with an action other than allow.
- Select ManageConfigurationSecurity ServicesURL Access Management.
- Under URL Access Management Profiles, select the checkbox next to the
best-practices profile and then Clone the
profile.The cloned profile appears under the profiles with the name best-practices-1.
- Select the best-practices-1 profile and rename it. For example, rename it to url-monitoring.
- Alert on all categories except
malware, command-and-control, and phishing, which should remain
blocked.
- Under Access Control, select all categories, then exclude malware, command-and-control, and phishing.
- With the categories still highlighted, click Set Access and choose Alert.
- Block access to
malware,
command-and-control, and
phishing other known dangerous URL
categories:
-
phishing
-
dynamic-dns
-
unknown
-
extremism
-
copyright-infringement
-
proxy-avoidance-and-anonymizers
-
newly-registered-domain
-
grayware
-
parked
-
- Save the profile.
- Apply the URL Access Management profile to Security policy rules that allow
traffic from clients in the trust zone to the internet.A URL Access Management Profile is only active when it’s included in a profile group that a Security policy rule references.Follow the steps to activate a URL Access Management profile (and any Security profile).Make sure the Source Zone in the Security policy rules you apply to URL Access Management profiles to is set to a protected internal network.
- Push Config to commit the configuration.
- Check the URL logs to see which website categories your users are accessing.
Blocked websites are also logged.For information on viewing the logs and generating reports, see Monitoring Web Activity.Select ActivityLog ViewerURL. URL Filtering reports provide a view of web activity in a 24-hour period.
- Next Steps:
- For everything that you don't allow or block, use risk categories to write simple policy based on website safety. PAN-DB categorizes every URL with a risk-level (high, medium, and low). While high and medium-risk sites are not confirmed malicious, they are closely associated with malicious sites. For example, they might be on the same domain as malicious sites or maybe they hosted malicious content until only very recently.You can take precautionary measures to limit your users’ interaction high-risk sites especially, as there might be some cases where you want to give your users access to sites that might also present safety concerns (for example, you might want to allow your developers to use developer blogs for research, yet blogs are a category known to commonly host malware).
- Pair URL filtering with User-ID to control web access based on organization or department and to block corporate credential submissions to unsanctioned sites:
- URL filtering prevents credential theft by detecting corporate credential submissions to sites based on the site 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 sites.
- Add or update a Security policy rule with the passive URL Access Management profile so that it applies to a department user group, for example, Marketing or Engineering. Monitor the department activity, and get feedback from department members to understand the web resources that are essential to the work they do.
- Consider all the ways of leveraging URL filtering to reduce your attack surface. For example, a school may use URL filtering to enforce strict safe search for students. Or, if you have a security operations center, you might give only threat analysts password access to compromised or dangerous sites for research.
- Follow URL filtering best practices.
Get Started with Advanced URL Filtering (PAN-OS & Panorama)
Follow these recommended practices for deploying Palo
Alto Networks URL filtering solution.
- Use Test A Site to check how PAN-DB categorizes a
specific website.You can also use the platform to request a categorization change for any website that you believe has been incorrectly categorized.
- Create a passive URL Filtering profile that alerts on all
categories.
- Select ObjectsSecurity ProfilesURL Filtering.
- Select the default profile, and then click Clone. The new profile will be named default-1.
- Select the default-1 profile and rename it. For example, rename it to URL-Monitoring.
- Configure the action for all categories to alert,
except for malware, command-and-control, and phishing, which should
remain blocked.
- In the section that lists all URL categories, select all categories and then de-select malware, command-and-control, and phishing.
- To the right of the Action column heading, mouse over and select the down arrow and then select Set Selected Actions and choose alert.
- Block access to known dangerous
URL categories. Block access to malware, phishing, dynamic-dns, unknown, command-and-control, extremism, copyright-infringement, proxy-avoidance-and-anonymizers, newly-registered-domain, grayware, and parked URL categories.
- Click OK to save the profile.
- Apply the URL Filtering profile to Security policy rules
that allow traffic from clients in the trust zone to the Internet.Make sure the Source Zone in the Security policy rules you add URL Access Management profiles to is set to a protected internal network.
- Select PoliciesSecurity. Then, select a Security policy rule to modify.
- On the Actions tab, edit the Profile Setting.
- For Profile Type, select Profiles. A list of profiles appears.
- For URL Filtering profile, select the profile you just created.
- Click OK to save your changes.
- Commit the configuration.
- View the URL filtering logs to see all of the website
categories that your users are accessing. The categories you’ve
set to block are also logged.For information on viewing the logs and generating reports, see Monitoring Web Activity.Select MonitorLogsURL Filtering. A log entry will be created for any website that exists in the URL filtering database that is in a category set to any action other than allow. URL Filtering reports give you a view of web activity in a 24-hour period. (MonitorReports).
- Next Steps:
- PAN-DB categorizes every URL with up to four categories, and every URL has a risk category (high, medium, and low). While high and medium-risk sites are not confirmed malicious, they are closely associated with malicious sites. For example, they might be on the same domain as malicious sites or maybe they hosted malicious content until only very recently. For everything that you do not allow or block, you can use risk categories to write simple policy rules based on website safety.You can take precautionary measures to limit your users’ interaction high-risk sites especially, as there might be some cases where you want to give your users access to sites that might also present safety concerns (for example, you might want to allow your developers to use developer blogs for research, yet blogs are a category known to commonly host malware).
- Pair URL filtering with User-ID to control web access based on organization or department and to block corporate credential submissions to unsanctioned sites:
- URL filtering prevents credential theft by detecting corporate credential submissions to sites based on the site 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 sites.
- Add or update a Security policy rule with the passive URL Filtering profile so that it applies to a department user group, for example, Marketing or Engineering (PoliciesSecurityUser). Monitor the department activity, and get feedback from department members to understand the web resources that are essential to the work they do.
- Consider all the ways of leveraging URL filtering to reduce your attack surface. For example, a school may use URL filtering to enforce strict safe search for students. Or, if you have a security operations center, you might give only threat analysts password access to compromised or dangerous sites for research.
- Follow URL filtering best practices.