The application must use the NotOnOrAfter condition when using the SubjectConfirmation element in a SAML assertion.

SAML is a standard for exchanging authentication and authorization data between security domains. SAML uses security tokens containing assertions to pass information about a principal (usually an end user) between a SAML authority, (identity provider), and a SAML consumer, (service provider). SAML assertions are usually made about a subject, (user) represented by the <Subject> element. When a SAML assertion is used with a <SubjectConfirmation> element, a begin and end time for the <SubjectConfirmation> should be set to prevent reuse of the message at a later time. Not setting a specific time period for the <SubjectConfirmation>, may grant immediate access to an attacker and result in an immediate loss of confidentiality.