Blocking Profiles allow you to identify specific file types
that you want to want to block or monitor. For most traffic (including
traffic on your internal network), block files that are known to
carry threats or that have no real use case for upload/download.
Currently, these include batch files, DLLs, Java class files, help
files, Windows shortcuts (.lnk), and BitTorrent files. Additionally,
to provide drive-by download protection, allow download/upload of
executables and archive files (.zip and .rar), but force users to
acknowledge that they are transferring a file so that they notice
that the browser is attempting to download something they were not
aware of. For policy rules that allow general web browsing, be stricter
with your file blocking because the risk of users unknowingly downloading
malicious files is much higher. For this type of traffic, attach
a more strict file blocking profile that also blocks portable executable
You can define your own custom File Blocking profiles
or choose one of the following predefined profiles when applying
file blocking to a Security policy rule. You can clone and edit
the predefined profiles, which are available with content release version
653 and later, and then follow File Blocking profile safe transition
steps to preserve application availability as you transition
to best practice file blocking settings:
basic file blocking
—Attach this profile
to the Security policy rules that allow traffic to and from less
sensitive applications to block files that are commonly included
in malware attack campaigns or that have no real use case for upload/download.
This profile blocks upload and download of PE files ( .scr, .cpl,
.dll, .ocx, .pif, .exe) , Java files (.class, .jar), Help files
(.chm, .hlp) and other potentially malicious file types, including
.vbe, .hta, .wsf, .torrent, .7z, .rar, .bat. Additionally, it prompts
users to acknowledge when they attempt to download encrypted-rar
or encrypted-zip files. This rule alerts on all other file types
to give you complete visibility into all file types coming in and
out of your network.
strict file blocking
—Use this stricter
profile on the Security policy rules that allow access to your most
sensitive applications. This profile blocks the same file types
as the other profile, and additionally blocks flash, .tar, multi-level
encoding, .cab, .msi, encrypted-rar, and encrypted-zip files.
predefined profiles are designed to provide the most secure posture
for your network. However, if you have business-critical applications
that rely on some of the applications that are blocked in these
default profiles, you can clone the profiles and modify them as
necessary. Make sure you only use the modified profiles for those
users who need to upload and/or download a risky file type. Additionally, to
reduce your attack surface, make sure you are using other security
measures to ensure that the files your users are uploading and downloading
do not pose a threat to your organization. For example, if you must
allow download of PE files, make sure you are sending all unknown PE files to WildFire foranalysis.
Additionally, maintain a strict URL filtering policy to ensure that
users cannot download content from web sites that have been known
to host malicious content.
Create the file blocking profile.
for the file blocking profile
) Enter a
Block users from downloading exe files from websites
) Specify that the profile is
Every virtual system (vsys) on a multi-vsys
—If cleared (disabled), the profile is available only to
the Virtual System selected in the
Every device group on Panorama
—If cleared (disabled),
the profile is available only to the Device Group selected in the
to prevent administrators from overriding the
settings of this file blocking profile in device groups that inherit
the profile. This selection is cleared by default, which means administrators
can override the settings for any device group that inherits the profile.
Configure the file blocking options.
and define a
rule for the profile.
for the rule,
or specify one or
Only web browsers can display the
response page (continue prompt) that allows users to confirm their
Choosing any other application results in blocked traffic for those
applications because there is no prompt displayed to allow users
or specify one or
, such as
For example, select
prompt users for confirmation before they are allowed to download
an executable (.exe) file. Alternatively, you could
specified files or you could configure the firewall to simply trigger
when a user downloads an executable
If a server sends an HTTP response header and the contents
of a file in different packets, the firewall blocks the file even
if the action for that file type is
to save the profile.
Apply the file blocking profile to a security policy
the file blocking profile you configured in the previous step. In
this example, the profile name is
To test your file blocking configuration, access an endpoint
PC in the trust zone of the firewall and attempt to download an
executable file from a website in the untrust zone; a response page
should display. Click
that you can download the file. You can also set other actions,
which do not provide an option for the user to continue the download.
The following shows the default response page for File Blocking:
) Define custom file blocking response
This allows you to provide more information to users when they see
a response page. You can include information such as company policy
information and contact information for a Helpdesk.
When you create a file blocking
profile with the
action, you can
choose only the
If you choose any other application, traffic that matches the security
policy will not flow through the firewall because users are not
prompted with an option to continue. Additionally, you need to configure and
enable a decryption policy for HTTPS websites.
Check your logs to determine the application
used when you test this feature. For example, if you are using Microsoft
SharePoint to download files, even though you are using a web-browser
to access the site, the application is actually