Simon Willison’s Weblog

24th January 2009 - Link Blog

OWASP: XSS Prevention Cheat Sheet. Comprehensive set of rules for avoiding XSS—there’s a bit more to it than just escaping all output variables, since you have to take markup context in to account.

Posted 24th January 2009 at 11:58 pm

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Changes in the system prompt between Claude Opus 4.6 and 4.7 - 18th April 2026
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This is a link post by Simon Willison, posted on 24th January 2009.

markup 8 owasp 4 security 597 xss 60

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