Description
A stored cross-site scripting (XSS) vulnerability affected the Markdown/RichText field preview renderer in Sveltia CMS.
The DOMPurify sanitization configuration used for Markdown previews explicitly permitted iframe elements without enforcing a sandbox attribute or restricting iframe sources.
Recommendation
Update the @sveltia/cms package to the latest compatible version. Followings are version details:
- Affected version(s): < 0.167.3
- Patched version(s): 0.167.3
References
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See something that needs correcting? Let us knowUpdated June 19, 2026