CVE-2026-34221
Severity CVSS v4.0:
HIGH
Type:
Unavailable / Other
Publication date:
31/03/2026
Last modified:
03/04/2026
Description
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.
Impact
Base Score 4.0
8.30
Severity 4.0
HIGH
Base Score 3.x
9.10
Severity 3.x
CRITICAL
Vulnerable products and versions
| CPE | From | Up to |
|---|---|---|
| cpe:2.3:a:mikro-orm:mikroorm:*:*:*:*:*:node.js:*:* | 6.6.10 (excluding) | |
| cpe:2.3:a:mikro-orm:mikroorm:*:*:*:*:*:node.js:*:* | 7.0.0 (including) | 7.0.6 (excluding) |
To consult the complete list of CPE names with products and versions, see this page



