{"id":"CVE-2026-34221","title":"MikroORM is a TypeScript ORM for Node.js based on Data Mapper, Unit of Work and Identity Map patterns","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 w…","severity":"critical","cvss":9.1,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H","cwe":["CWE-1321"],"vendor":"mikro-orm","product":"mikroorm","affected":["mikroorm < 6.6.10","mikroorm >= 7.0.0, < 7.0.6"],"patched":["mikroorm 7.0.6"],"published":"2026-03-31","updated":"2026-07-24","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-34221","references":[{"url":"https://github.com/mikro-orm/mikro-orm/security/advisories/GHSA-qpfv-44f3-qqx6","label":"security-advisories@github.com"}],"tags":["nvd"],"epss":0.00511,"epssPercentile":0.40972,"ingestedAt":"2026-07-24T20:38:02.389Z","slug":"CVE-2026-34221","body":"## Overview\n\nMikroORM 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.\n\n## Affected\n\n- `mikroorm < 6.6.10`\n- `mikroorm >= 7.0.0, < 7.0.6`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `mikroorm 7.0.6`","depth":"midnight","depthScore":50,"depthScoreParts":{"impact":50.1,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}