fix: escape user input in md2html to prevent XSS in live preview#244
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mrunalC27 wants to merge 1 commit into
Open
fix: escape user input in md2html to prevent XSS in live preview#244mrunalC27 wants to merge 1 commit into
mrunalC27 wants to merge 1 commit into
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Description
Closes #243.
md2html()only escaped content inside fenced code blocks, leaving every other user-entered field (project name, description, features, etc.) unescaped before being inserted into the HTML rendered viadangerouslySetInnerHTMLinPreviewPanel.jsx.This allowed arbitrary HTML/JS typed into any field to execute immediately in the live preview.
Fix
Escape the full markdown input up front with the existing
esc()helper, before any of the markdown-to-HTML transforms run — the same approach already used for code blocks.esc()only touches&,<,>, so it doesn't interfere with any markdown syntax characters (*,#,`,[,],(,),|,-) that the transform pipeline relies on.Testing
<img src=x onerror=alert(1)>now renders as literal visible text instead of executing.&in query params), tables, and fenced code blocks all still render correctlyand are not double-escaped.
npm run buildpasses with no errors.Note
This was previously self-XSS only (no import/share-link feature currently loads another user's data), but is worth fixing regardless
as defense-in-depth before any such feature is added.