FrameHanger: Evaluating and Classifying Iframe Injection at Large Scale.

Iframe is a web primitive frequently used by web developers to integrate content from third parties. It is also extensively used by web hackers to distribute malicious content after compromising vulnerable sites. Previous works focused on page-level detection, which is insufficient for Iframe-specific injection detection. As such, we conducted a comprehensive study on how Iframe is included by websites around Internet in order to identify the gap between malicious and benign inclusions. By studying the online and offline inclusion patterns from Alexa top 1M sites, we found benign inclusion is usually regulated. Driven by this observation, we further developed a tag-level detection system named FrameHanger which aims to detect injection of malicious Iframes for both online and offline cases. Different from previous works, our system brings the detection granularity down to the tag-level for the first time without relying on any reference. The evaluation result shows FrameHanger could achieve this goal with high accuracy.