CVE-2026-34221 — MikroORM has Prototype Pollution in Utils.merge

Description (CNA)

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.

Affected (CNA)

Vendor / product	Versions
mikro-orm / mikro-orm	affected < 6.6.10; affected >= 7.0.0-rc.0, < 7.0.6

CWE

CWE-1321

References

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

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.