Inherited Vulnerabilities: Javascript Engine V4 secure coding compared to Googles V8

In 2013, the Qt Project announced a move away from Google's V8 JavaScript engine to their own internal V4 JavaScript engine. Despite this, even today Qt still contains a V8 interpretation layer and V8 code in other parts of Qt. This paper aims to investigate why the decision to change interpreters was made and also to evaluate the aspects of Qt interpreted by V4 and what is interpreted by V8. With this defined, differences in secure coding techniques between these systems is examined and highlighted and why these techniques are important in the Qt environment.