An attacker manipulates the headers and content of an email message by
						injecting data via the use of delimeter characters native to the protocol.
						Many applications allow users to send email messages by filling in fields.
						For example, a web site may have a link to "share this site with a friend"
						where the user provides the recipient's email address and the web
						application fills out all the other fields, such as the subject and body. In
						this pattern, an attacker adds header and body information to an email
						message by injecting additional content in an input field used to construct
						a header of the mail message. This attack takes advantage of the fact that
						RFC 822 requires that headers in a mail message be separated by a carriage
						return. As a result, an attacker can inject new headers or content simply by
						adding a delimiting carriage return and then supplying the new heading and
						body information. This attack will not work if the user can only supply the
						message body since a carriage return in the body is treated as a normal
						character.