Can a literature review be a "master's thesis"?
At least in my Faculty (of Computer Science), a master thesis can be "just" a literature review. A literature review can be an important contribution, and is part of what is usually called secondary research.

However, you should consider performing a systematic literature review, which is a literature review comprising several analytic and precise steps to enhance the reliability of the study. A systematic literature review is a time consuming research activity but a very useful one. Please verify that such a review has not already been conducted recently, before starting it by your own.

Systematic reviews are publishable research and often get many citations. As for thesis, I think that any publishable research activity can be a student's master thesis. However, ask your (potential) advisor.