The Internet Key Exchange version 1 (IKEv1) implementations in Fortinet FortiOS 2.50, 2.80 and 3.0, FortiClient 2.0,; and FortiManager 2.80 and 3.0 allow remote attackers to cause a denial of service (termination of a process that is automatically restarted) via IKE packets with invalid values of certain IPSec attributes, as demonstrated by the PROTOS ISAKMP Test Suite for IKEv1.  NOTE: due to the lack of details in the vendor advisory, it is unclear which of CVE-2005-3666, CVE-2005-3667, and/or CVE-2005-3668 this issue applies to.