MediumGHSA-wv8q-r932-8hc7CVE-2022-25875SNYK-JS-SVELTE-2931080

Svelte vulnerable to XSS when using objects during server-side rendering

Published 13 Jul 2022 · Updated 8 Jul 2026

Affected package

Affected: <3.49.0
Fixed in: 3.49.0

Update to the fixed version for your release line, for example:npm install svelte@3.49.0

Details

The package svelte before 3.49.0 is vulnerable to Cross-site Scripting (XSS) due to improper input sanitization and to improper escape of attributes when using objects during SSR (Server-Side Rendering). Exploiting this vulnerability is possible via objects with a custom toString() function.

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References

Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.