CVE-2026-27121 (GCVE-0-2026-27121)

Vulnerability from cvelistv5 – Published: 2026-02-20 22:27 – Updated: 2026-02-23 19:34
VLAI?
Title
Svelte affected by cross-site scripting via spread attributes in Svelte SSR
Summary
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.
Severity ?
5.1 (Medium)
CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:L/VI:N/VA:N/SC:H/SI:H/SA:N
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version
sveltejs svelte Affected: < 5.51.5
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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