CVE-2026-27121

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.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/sveltejs/svelte/security/advisories/GHSA-f7gr-6p89-r883	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:svelte:svelte:*:*:*:*:*:node.js:*:*

History

23 Feb 2026, 20:53

Type	Values Removed	Values Added
CPE		cpe:2.3:a:svelte:svelte::::::node.js::*
First Time		Svelte svelte Svelte
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.4
References	~~() https://github.com/sveltejs/svelte/security/advisories/GHSA-f7gr-6p89-r883 -~~	() https://github.com/sveltejs/svelte/security/advisories/GHSA-f7gr-6p89-r883 - Vendor Advisory

20 Feb 2026, 23:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-20 23:16

Updated : 2026-02-23 20:53

NVD link : CVE-2026-27121

Mitre link : CVE-2026-27121

CVE.ORG link : CVE-2026-27121

JSON object : View

Products Affected

svelte

svelte

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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