The administration protocol for Kerio WinRoute Firewall 6.x up to 6.0.10, Personal Firewall 4.x up to 4.1.2, and MailServer up to 6.0.8 allows remote attackers to cause a denial of service (CPU consumption) via certain attacks that force the product to "compute unexpected conditions" and "perform cryptographic operations."
http://www.securityfocus.com/archive/1/397220