ZyXEL Communications USG FLEX H Series - Page 290

Chapter 18 Anti-Malware
USG FLEX H Series User’s Guide
290
• SMTP (Simple Mail Transfer Protocol)
• POP3 (Post Office Protocol version 3)
The Zyxel Device records the orders of packets in TCP connection-oriented sessions to check for
matching malware signatures. The order of non-setup packets such as SYN, ACK and FIN is ignored.
Anti-Malware Scanning Procedure:
1 The Zyxel Device uses Cloud Query to forward the file’s hash value to Defend Center.
2 Defend Center checks its database for malware signature matches and sends the results back to the
Zyxel Device.
If a malware signature is matched, the actions you specify for identified malware will be applied. If
Destroy infected file is enabled, the file will be modified. Logs/alerts will be sent according to your
settings.
Note: The receiver is not notified if a file is modified by the Zyxel Device. If the file cannot be
used, the receiver should contact the Zyxel Device administrator to confirm if the Zyxel
Device modified the file by checking the logs.
File Scanning Cloud Query Supported File Types
At the time of writing, the following file types are supported:
Notes About the Zyxel Device Anti-Malware
The following lists important notes about the Zyxel Device’s anti-malware feature:
1 Zyxel’s anti-malware feature can detect polymorphic malware (see Section 18.1 on page 288).
2 When malware is detected, a log is created or an alert message is sent to the administrator depending
on your log settings.
3 Changes to the Zyxel Device’s anti-malware settings only affect new sessions, not sessions that already
existed before you applied the changed settings.
4 Enabling Cloud Query may affect file transfer speeds.
5 The Zyxel Device does not scan the following file/traffic types:
Table 147 File Scanning Cloud Query Supported File Types
• 7z Archive (7z) • AVI Video (avi) •BMP Image (bmp) • BZ2 Archive (bz2)
• Executables (exe) • Macromedia Flash
Data (swf)
• GIF Image (gif) •GZ Archive (gz)
•JPG Image (jpg) •MOV Video (mov) • MP3 Audio (mp3) • MPG Video (mpg)
• MS Office
Document (doc...)
• PDF Document
(pdf)
•PNG Image (png) • RAR Archive (rar)
•RM Video (rm) •RTF Document (rtf) •TIFF Image (tif) •WAV Audio (wav)
• ZIP Archive (zip)