Vansh and Vaibhuv two Indian Hacker found a XSS vulnerability in world famous site Paypal. Paypal is affected by an XSS vulnerability where it fails to validate input. One can add arbitrary javascript with no need for any filter evasion.
This is a serious security issue, with potential implications that are only starting to be understood. However, it is critical to realize that this problem does not expose any way to break into the server itself. What it allows is for malicious attackers to potentially take control of the interaction between a user and a website. It is likely that the most serious thing that an attacker can potentially do in this situation is change how a page appears to a particular user.