Microsoft .NET Framework 2.0 SP2, 3.5, 3.5 SP1, 3.5.1, 4, and 4.5 allows remote attackers to cause a denial of service (application crash or hang) via crafted character sequences in JSON data, aka "JSON Parsing Vulnerability."
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.