Description
Errors from transformError were not correctly escaped prior to being embedded in the HTML output, causing potential HTML injection and XSS if attacker-controlled content is returned from transformError.
Recommendation
Update the svelte package to the latest compatible version. Followings are version details:
- Affected version(s): >= 5.53.0, < 5.53.5
- Patched version(s): 5.53.5
References
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See something that needs correcting? Let us knowUpdated February 26, 2026