# A Systematic Survey of Multi-Factor Authentication for Cloud Infrastructure
## 5 Conclusions and Future Work  
MFA is an effective means of increasing the difficulty for intruders to gain unauthorized access to the system. MFA ensures secured access to resources for interactions \begin{table}
\begin{tabular}{p{142.3 pt} p{142.3 pt}} \hline \hline
**Threat** & **Envisaged Effect** \\ \hline \multirow{2}{*}{_Biometric Spoofing_} & Biometric authentication mechanisms may be vulnerable to spoofing attacks, where attackers create fake biometric data to fool the authentication system. \\ \hline \multirow{2}{*}{_Credential stuffing_} & Attackers may use stolen MFA credentials to gain access to other accounts belonging to the same user. \\ \hline \multirow{2}{*}{_Denial of Service (DoS) attacks_} & Attackers may launch DoS attacks against the authentication system, preventing legitimate users from accessing their accounts. \\ \hline \multirow{2}{*}{_Insider Threats_} & Employees or contractors with access to sensitive systems may abuse their privileges to bypass MFA or steal MFA credentials. \\ \hline \multirow{2}{*}{_Malware_} & Malicious software such as keyloggers or screen capture tools may be used to steal MFA credentials from infected devices. \\ \hline \multirow{2}{*}{_Man-in-the-middle attacks_} & Attackers may intercept communication between users and the authentication system, allowing them to steal MFA credentials. \\ \hline \multirow{2}{*}{_Social Engineering_} & Attackers may attempt to trick users into divulging their MFA credentials through phishing attacks or other forms of social engineering. \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Prominent Threats to MFA Implementation. between users and cloud infrastructure by facilitating efficient, user-friendly, and trustworthy authentication whenever accessing a service. This paper presented a systematic approach to determine a factor, particularly biometric face recognition, without disturbing a logged-in user from ongoing work and without requiring additional hardware and software for the system. Performance consistency and efficiency should be further experimentally established for various associated phases of MFA system functioning. This research effort aims to prevent impersonation attacks on the system since the uniqueness of the user's biometric facial characteristics is being considered as a factor of authentication [97] as a part of the MFA process. This is to avoid dependency on TTP and make use of a DLT-based storage.Having credentials with advanced cryptographic means, an MFA solution based on the Physically Unclonable Function (PUF) [98] would have an edge over the classical solutions. However, needing further exploration is the trade-off between performance and security of user authentication using state-of-the-art facial recognition based on Non-Convoluted Neural Network (Non-CNN) and Convoluted Neural Network (CNN) algorithms [99] against impersonation attacks. Such effort is expected to handle the potential spoofing attacks by means of a liveness check of the user and provide a means of secured user authentication for the cloud environment and multi-cloud infrastructure. MFA is vulnerable to social engineering attacks and many researchers are continuously exploring the options for its detection and prevention. Similarly, a simple DoS attack, by blocking the second authentication channel, could also affect the system effectiveness. The usage of cryptography techniques coupled with suitable measures, such as Network Traffic Monitoring, Implementing Traffic Load Balance Functionality, Using of Content Delivery Networks Functionality, and especially Implementing Data-Rate Limiting Approach to and from suspected IP addresses, is a suggested way to tackle possible DoS attacks on MFA systems. Conceptualization, S.P.O. and S.P. ; methodology, S.P.O., C.H. and M.G. ; writing--original draft preparation, S.P.O. ; validation, S.P., C.H. and M.G. ; formal analysis, S.P.O. ; investigation, S.P. and C.H. ; writing--review and editing, M.G. ; visualization, S.P.O. ; supervision, S.P.O. and M.G.