It is essential to solve the problem due to password fatigue in order to increase the security of the transactions on the Web and secure the users’ account and information. Web Single Sign-On is one of the techniques that have been created to solve these issues. Unfortunately, this method creates new opportunities for hackers. The Liberty Alliance and OpenID are two of the most known Web Single Sign-On frameworks. This work intends to review the strengths and the weaknesses of both regarding their ability to protect the confidentiality, integrity and availability of the users’ information, by studying their aptitude to prevent some of the most dangerous attacks on the web. The analysis of the results shows that Liberty Alliance has created a strong infrastructure in order to mitigate those attacks. Consequently, this framework protects the confidentiality, integrity and availability of the users’ information more efficiently than OpenID. On the other hand, this latter shows significant weaknesses that compromises the confidentiality, integrity and availability of the users’ information.