According to the CRISC Review Manual1, single sign-on (SSO) is a method of authentication that allows a user to access multiple systems or applications with a single set of credentials. SSO can improve user convenience and productivity, but it also introduces some security risks. The greatest concern as a result of a single sign-on implementation is that unauthorized access may be gained to multiple systems, as this can compromise the confidentiality, integrity, and availability of the data and resources stored on those systems. If an attacker obtains the SSO credentials of a user, either by phishing, malware, or other means, they can Laccess all the systems or applications that the user is authorized for, without any additional authentication or verification. This can expose the organization to various threats, such as data leakage, theft, loss, corruption, manipulation, or misuse2345. References = CRISC Review Manual1, page 240, 253.