XSS Cross-Site Scripting Detection

Problem context

Web application XSS testing often stops too early at “I found one reflected point.” In real assessments, stored XSS, reflected XSS, DOM XSS, and blind XSS rarely appear as clean, isolated cases. CSP, legacy XSS filters, event handlers, DOM clobbering, and mutation XSS can change whether a payload actually executes. Without a stable checklist, testers can miss bypass paths or fail to connect script execution to higher-impact outcomes such as session hijacking, phishing, or keylogging.

How it works

This skill organizes XSS testing into an operational checklist. Once active, it expects the agent to follow the methodology item by item:

• Discovery: inspect input-to-render paths for stored XSS, reflected XSS, DOM XSS, and blind XSS.
• Bypasses: evaluate polyglot payloads, CSP bypass, XSS filter bypass, and event handler injection.
• Impact: connect script execution to escalation paths such as session hijack, phishing, and keylogging.
• Process control: track completed checklist items and propose next steps based on findings.

It is suitable for authorized web application testing, security assessments, and bug bounty workflows. Users must still confirm authorization before running payloads against a target. Whether a specific bypass works depends on the browser, CSP policy, front-end framework, and backend filtering, so checklist techniques should not be treated as guaranteed vulnerabilities.