CVE-2026-34221

MikroORM is a TypeScript ORM for Node.js based on Data Mapper, Unit of Work and Identity Map patterns. Prior to versions 6.6.10 and 7.0.6, a prototype pollution vulnerability exists in the Utils.merge helper used internally by MikroORM when merging object structures. The function did not prevent special keys such as __proto__, constructor, or prototype, allowing attacker-controlled input to modify the JavaScript object prototype when merged. This issue has been patched in versions 6.6.10 and 7.0.6.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/mikro-orm/mikro-orm/security/advisories/GHSA-qpfv-44f3-qqx6	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mikro-orm:mikroorm::::::node.js::*
	cpe:2.3:a:mikro-orm:mikroorm::::::node.js::*

History

03 Apr 2026, 15:13

Type	Values Removed	Values Added
References	~~() https://github.com/mikro-orm/mikro-orm/security/advisories/GHSA-qpfv-44f3-qqx6 -~~	() https://github.com/mikro-orm/mikro-orm/security/advisories/GHSA-qpfv-44f3-qqx6 - Vendor Advisory
First Time		Mikro-orm Mikro-orm mikroorm
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.1
CPE		cpe:2.3:a:mikro-orm:mikroorm::::::node.js::*

31 Mar 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-31 16:16

Updated : 2026-04-03 15:13

NVD link : CVE-2026-34221

Mitre link : CVE-2026-34221

CVE.ORG link : CVE-2026-34221

JSON object : View

Products Affected

mikro-orm

mikroorm

CWE

CWE-1321

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

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