A bug bounty hunter describes finding 5 stored XSS vulnerabilities on a private program worth $1,016.66 each, including techniques for bypassing input filters through payload placement, encoding variations (<), file upload abuse (.xhtml), and filter evasion by targeting unsanitized HTML in notifications.
Researcher bypassed XSS protection filters using an iframe payload with data URI encoding to achieve stored XSS in a comment box, earning a $150 bounty within 30 minutes. The payload exploited the target's allowlisting of iframe tags while blocking standard script injection vectors.
Researcher discovered a reflected XSS vulnerability on Amazon's ad system domain (ws-na.amazon-adsystem.com) via the tracking_id parameter, then bypassed Amazon's initial fix using an alternative payload technique.
A stored XSS vulnerability bypassed input filters by injecting malicious HTML attributes into an input field. The attacker circumvented tag filtering and character encoding by using OnMouseOver event handlers with backtick-quoted function calls to execute JavaScript via user interaction.
A researcher discovered stored XSS vulnerability in a file upload feature restricted to CSV files by bypassing server-side XSS filters using a polyglot payload combining HTML/SVG tags and event handlers.