CVE-2026-27122

svelte performance oriented web framework. Prior to 5.51.5, when using <svelte:element this={tag}> in server-side rendering, the provided tag name is not validated or sanitized before being emitted into the HTML output. If the tag string contains unexpected characters, it can result in HTML injection in the SSR output. Client-side rendering is not affected. 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-m56q-vw4c-c2cp	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
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.4
References	~~() https://github.com/sveltejs/svelte/security/advisories/GHSA-m56q-vw4c-c2cp -~~	() https://github.com/sveltejs/svelte/security/advisories/GHSA-m56q-vw4c-c2cp - Vendor Advisory
First Time		Svelte svelte Svelte
CPE		cpe:2.3:a:svelte:svelte::::::node.js::*

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-2026-27122

Mitre link : CVE-2026-27122

CVE.ORG link : CVE-2026-27122

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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