An issue was discovered in certain Apple products. iOS before 10.3.3 is affected. watchOS before 3.2.3 is affected. The issue involves the "Messages" component. It allows remote attackers to cause a denial of service (memory consumption and application crash).
Apple Security Advisory 2017-07-19-3 - watchOS 3.2.2 is now available and addresses buffer overflow, memory corruption, and various other vulnerabilities.