Description
An XSS vulnerability exists in Svelte 5.46.0-2 resulting from improper escaping of hydratable keys. If these keys incorporate untrusted user input, arbitrary JavaScript can be injected into server-rendered HTML.
Recommendation
Update the svelte package to the latest compatible version. Followings are version details:
- Affected version(s): >= 5.46.0, <= 5.46.3
- Patched version(s): 5.46.4
References
Related Issues
- jsondiffpatch is vulnerable to Cross-site Scripting (XSS) via HtmlFormatter::nodeBegin - CVE-2025-9910
- `vega-functions` vulnerable to Cross-site Scripting via `setdata` function - CVE-2025-66648
- Trix vulnerable to Cross-site Scripting on copy & paste - CVE-2025-46812
- @sveltejs/kit vulnerable to Cross-site Scripting via tracked search_params - CVE-2025-32388
- Tags:
- npm
- svelte
Anything's wrong? Let us know Last updated on January 19, 2026