Vulnerability library
Security checkOctober 20, 2026

ApostropheCMS sanitize-html: SMIL animation namespace-prefix bypass allows javascript: URI injection (XSS)

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Low severitynpmsanitize-html

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Description

sanitize-html 2.17.7 introduced animatesUrlAttribute() to block SVG animation elements (animate, animateColor, animateMotion, animateTransform, set) when their attributeName targets a URL sink like href. However, this check is bypassed when the animation element uses a namespace prefix (e.g., svg:animate instead of animate).

Recommendation

Update the sanitize-html package to the latest compatible version. Followings are version details:

  • Affected version(s): >= 2.17.7, < 2.18.0
  • Patched version(s): 2.18.0

References

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Related Issues

See something that needs correcting? Let us knowUpdated October 20, 2026