CVE-2026-27121 — Svelte affected by cross-site scripting via spread attributes in Svelte SSR
svelte performance oriented web framework. Versions of svelte prior to 5.51.5 are vulnerable to cross-site scripting (XSS) during server-side rendering. When using spread syntax…
Published: 2026-02-20 · CVSS: 5.1 · CVSS 4.0
svelte performance oriented web framework. Versions of svelte prior to 5.51.5 are vulnerable to cross-site scripting (XSS) during server-side rendering. When using spread syntax to render attributes from untrusted data, event handler properties are included in the rendered HTML output. If an application spreads user-controlled or external data as element attributes, an attacker can inject malicious event handlers that execute in victims' browsers. This vulnerability is fixed in 5.51.5.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7