Svelte 5.46.0 - Hydratable Key Script-Breakout XSS (SSR)
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An SSR XSS exists in async hydration when attacker‑controlled keys are passed to hydratable. The key is embedded inside a <script> block without HTML‑safe escaping, allowing </script> to terminate the script and inject arbitrary JavaScript. This enables remote script execution in users' browsers, with potential for session theft and account compromise. This issue affects Svelte: from 5.46.0 before 5.46.3.
No remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
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