Security: Potential XSS risk in markdown rendering helper if reused with untrusted input#478
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gre merged 1 commit intogre:masterfrom Apr 8, 2026
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…per if The markdown utility renders markdown through `remark().use(remark-react)` and returns React elements. If this helper is ever called with user-controlled markdown (instead of static literals), untrusted markdown/HTML handling may introduce scriptable content depending on parser/plugin behavior and version defaults. Affected files: markdown.js Signed-off-by: tuanaiseo <221258316+tuanaiseo@users.noreply.github.com>
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Problem
The markdown utility renders markdown through
remark().use(remark-react)and returns React elements. If this helper is ever called with user-controlled markdown (instead of static literals), untrusted markdown/HTML handling may introduce scriptable content depending on parser/plugin behavior and version defaults.Severity:
mediumFile:
packages/cookbook/src/markdown.jsSolution
Enforce sanitization explicitly by adding a sanitizer pipeline (e.g.,
rehype-sanitize/equivalent) and disallow raw HTML. Document that this helper must only process trusted content unless sanitization is enabled.Changes
packages/cookbook/src/markdown.js(modified)Testing