Harden XSS markdown renderer fix
Hard Security Basics arena: HTML sanitization, safe links, script stripping, and regression payloads
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Missing prerequisites: security-easy-xss-markdown-renderer
A profile bio renderer supports markdown, but a report shows JavaScript executing inside preview cards. You are working inside a secure engineering review room, and the arena only clears when the result is safe, deterministic, and explainable.
Learn to apply HTML sanitization, safe links, script stripping, and regression payloads in a secure engineering review room while explaining the invariant, safety constraints, and hidden edge cases.
- Demonstrates HTML sanitization, safe links, script stripping, and regression payloads
- Handles the visible sample and hidden edge cases
- Keeps output deterministic and explainable
- Avoids unsafe dynamic execution
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Genie Mentor Core
Hint protocol / contextual guardrails active