Grandstream BudgeTone 101 and 102 running firmware 1.0.6.7 and possibly earlier versions, allows remote attackers to cause a denial of service (device hang or reboot) via a large UDP packet to port 5060.
Grandstream BudgeTone (BT) 100 Voice over IP (VoIP) phones do not properly check the Call-ID, branch, and tag values in a NOTIFY message to verify a subscription, which allows remote attackers to spoof messages such as the "Messages waiting" message.