CVE-2026-34221CRITICAL 9.1EPSS p29.4%
CVE-2026-34221CVE-2026-34221
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.
Scoring
| CVSS 3.1 | 9.1 (CRITICAL) |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H |
| EPSS | 0.38% probability of exploitation · percentile 29.4% · 2026-06-18T12:00:27Z |
| Published | 2026-03-31 |
| Last modified | 2026-04-03 |
Underlying weaknesses· 1
References
1
| Type | Target | Confidence | Tier |
|---|---|---|---|
| Weakness | Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')cwe-1321 | 0% | live |
Related by meaning· 6
Nearest entities by semantic similarity across the cs-graph corpus.