Security risk found in message "Nadia at sheltech-bd.com"

[Symantec.Endpoint.Protection at mail.sheltech-bd.com]

Symantec Endpoint Protection found a security risk in an attachment you (freebsd-doc at freebsd.org) sent to nadia at sheltech-bd.com.

To ensure the recipients are able to use the files you sent, perform a virus scan on your computer, clean any infected files, then resend this attachment.
Attachment: attachment.zip
Security risk detected: W32.Mydoom.M at mm
Action taken: Cleaned by Deletion
File status: Cleaned by Deletion