Microsoft .NET Framework 1.0 SP3, 1.1 SP1, 2.0 SP2, 3.0 SP2, 3.5 SP1, 3.5.1, and 4 does not properly serialize input data, which allows remote attackers to execute arbitrary code via (1) a crafted XAML browser application (aka XBAP) or (2) a crafted .NET Framework application, aka ".NET Framework Serialization Vulnerability."
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A15554
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2012/ms12-035
http://www.us-cert.gov/cas/techalerts/TA12-129A.html
http://www.securitytracker.com/id?1027036