SonicWALL NSA 240 Getting Started Manual page 46

Enabling Gateway Anti-Virus
To enable Gateway Anti-Virus in SonicOS:
1. Navigate to the Security Services > Gateway Anti-Virus
page. Select the Enable Gateway Anti-Virus checkbox.
2. Select the Enable Inbound Inspection checkboxes for the
protocols to inspect. By default, SonicWALL GAV inspects
all inbound HTTP, FTP, IMAP, SMTP and POP3 traffic.
CIFS/NetBIOS can optionally be enabled to allow access
to shared files. Generic TCP Stream can optionally be
enabled to inspect all other TCP based traffic, such as non-
standard ports of operation for SMTP and POP3, and IM
and P2P protocols.
3. Enabling Outbound Inspection for SMTP scans mail for
viruses before it is delivered to an internally hosted SMTP
server.
4. For each protocol you can restrict the transfer of files with
specific attributes by clicking on the Settings button under
the protocol. In the Settings dialog box, you can configure
the following:
• Restrict Transfer of password-protected Zip files -
Disables the transfer of password protected ZIP files
over any enabled protocol. This option only functions
on protocols that are enabled for inspection.
• Restrict Transfer of MS-Office type files containing
macros (VBA 5 and above) - Disables the transfers of
any MS Office files that contain VBA macros.
• Restrict Transfer of packed executable files (UPX,
FSG, etc.) - Disables the transfer of packed
executable files. Packers are utilities that compress
and encrypt executables. Although there are legitimate
applications for these, they can be used with the intent
of obfuscation, and can make the executables less
detectable by anti-virus applications. The packer adds
a header that expands the file in memory, and then
executes that file. SonicWALL Gateway Anti-Virus
currently recognizes the most common packed
formats: UPX, FSG, PKLite32, Petite, and ASPack,
5. Click Configure Gateway AV Settings. The Gateway AV
Settings window allows you to configure clientless
notification alerts and create a SonicWALL GAV exclusion
list.
SonicWALL NSA 240 Getting Started Guide Page 41