Malformed Email - 3Com 3CR3MFA-92 User Manual

44 C 3: C
HAPTER ONFIGURING

Malformed Email

M S
AIL ECURITY
Many viruses try to elude virus scanners by concealing themselves in
malformed messages. The scanning engines cannot detect the
attachment and pass the complete message through to an internal
server.
Some mail clients try to rebuild malformed messages and may rebuild or
activate a virus-infected attachment. Other types of malformed messages
are designed to attack mail servers directly. These types of messages are
often used in denial-of-service (DoS) attacks.
The 3Com Email Firewall analyzes each message with very extensive
integrity checks. Malformed messages are quarantined if they cannot be
processed.
Select Mail Delivery -> Malformed Email from the menu to configure
malformed email checks.
Enable malformed scanning — Select this option to enable scanning
■
for malformed emails.
Enable NULL Character Detect — Select this option to enable null
■
character detection. Any messages with null characters in them (a byte
value of 0) will be considered a malformed message.