CVE-2006-1966
An unspecified Fortinet product, possibly Fortinet28, allows remote attackers to cause a denial of service via a "small synflood" to the SMTP port (TCP port 25), as demonstrated by a 10-microsecond wait between sending packets. NOTE: this issue has been disputed in followup posts that suggest that a protection feature is triggering a RST.
Date published : 2006-04-21
http://www.securityfocus.com/archive/1/431404/100/0/threaded
http://archives.neohapsis.com/archives/fulldisclosure/2006-04/0449.html