VYPR
Moderate severityNVD Advisory· Published Feb 20, 2026· Updated Feb 23, 2026

Svelte affected by cross-site scripting via spread attributes in Svelte SSR

CVE-2026-27121

Description

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.

Affected packages

Versions sourced from the GitHub Security Advisory.

PackageAffected versionsPatched versions
sveltenpm
< 5.51.55.51.5

Affected products

1

Patches

0

No patches discovered yet.

Vulnerability mechanics

AI mechanics synthesis has not run for this CVE yet.

References

3

News mentions

0

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