Here you can find the latest changelogs Antimalware (Antivirus + Antispyware) updates for Microsoft Security Essentials, Windows Defender and ForeFront clients.
http://www.microsoft.com/security/portal/definitions/whatsnew.aspx
You may be asked to log in with your Microsoft Account.
http://www.microsoft.com/security/portal/definitions/whatsnew.aspx
You may be asked to log in with your Microsoft Account.