CVE-2026-30226

Svelte devalue is a JavaScript library that serializes values into strings when JSON.stringify isn't sufficient for the job. In devalue v5.6.3 and earlier, devalue.parse and devalue.unflatten were susceptible to prototype pollution via maliciously crafted payloads. Successful exploitation could lead to Denial of Service (DoS) or type confusion. This vulnerability is fixed in 5.6.4.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/sveltejs/devalue/security/advisories/GHSA-cfw5-2vxh-hr84	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

17 Mar 2026, 19:07

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
CPE		cpe:2.3:a:svelte:devalue::::::node.js::*
First Time		Svelte Svelte devalue
References	~~() https://github.com/sveltejs/devalue/security/advisories/GHSA-cfw5-2vxh-hr84 -~~	() https://github.com/sveltejs/devalue/security/advisories/GHSA-cfw5-2vxh-hr84 - Vendor Advisory
Summary		(es) Svelte devalue es una biblioteca JavaScript que serializa valores en cadenas cuando JSON.stringify no es suficiente para la tarea. En devalue v5.6.3 y anteriores, devalue.parse y devalue.unflatten eran susceptibles a la contaminación de prototipos a través de cargas útiles creadas maliciosamente. La explotación exitosa podría conducir a denegación de servicio (DoS) o confusión de tipos. Esta vulnerabilidad está corregida en 5.6.4.

11 Mar 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-11 18:16

Updated : 2026-03-17 19:07

NVD link : CVE-2026-30226

Mitre link : CVE-2026-30226

CVE.ORG link : CVE-2026-30226

JSON object : View

Products Affected

svelte

devalue

CWE

CWE-1321

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

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