A method and system for document security are described. The method decrypts a key-map file located a composite document with embedded access control, decrypts a content part from the composite document with embedded access control, wherein the key-map file provides a key to access the content part, loads the content part in decrypted form into a document serialization maintained in a transient memory where the content part in decrypted form is maintained exclusively in the transient memory, and erases the content part in decrypted form upon termination of a program to access the decrypted content part from the document serialization.