CVE-2026-34221 (GCVE-0-2026-34221)

Vulnerability from cvelistv5 – Published: 2026-03-31 15:17 – Updated: 2026-03-31 18:52
VLAI
Title
MikroORM has Prototype Pollution in Utils.merge
Summary
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.
Severity
8.3 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:L/SA:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-31 18:50 UTC
CWE
  • CWE-1321 - Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
Assigner
References
Impacted products
Vendor Product Version CPE status
mikro-orm mikro-orm Affected: < 6.6.10
Affected: >= 7.0.0-rc.0, < 7.0.6
guessed Create a notification for this product.
Show details on NVD website
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