Stored XSS on reports.

How it was found

Summary: Stored XSS can be submitted on reports, and anyone who will check the report the XSS will trigger.

Description: Stored XSS, also known as persistent XSS, is the more damaging than non-persistent XSS. It occurs when a malicious script is injected directly into a vulnerable web application.

Steps To Reproduce:

1. Go to https://app.mopub.com/reports/custom/
2. Click New network report.
3. On the name, enter payload: "><img src=x onerror=alert(document.domain)>
4. Click Run and save then XSS will trigger.

Demonstration of the vulnerability: PoC: ████

Tested on Firefox and chrome.

Impact

The attacker can steal data from whoever checks the report.