The Holy Quran and Hadith are the two main sources of legislation and guidelines for Muslims to shape their lives. The daily activities, sayings, and deeds of the Holy Prophet Muhammad (PBUH) are called Hadiths. Hadiths are the optimal practical descriptions of the Holy Quran. Technological advancements of information and communication technologies (ICT) have revolutionized every field of daily life, including digitizing the Holy Quran and Hadith. Available online contents of Hadith are obtained from different sources. Thus, alterations and fabrications of fake Hadiths are feasible. Authentication of these online available Hadith contents is a complex and challenging task and a crucial area of study in Islam. Few Hadith authentication techniques and systems are proposed in the literature. In this study, we have surveyed all techniques and systems, which are proposed for Hadith authentication. Furthermore, classification, open challenges, and future research directions related to Hadith authentication are identified.