{"id":"CVE-2026-34221","aliases":["GHSA-qpfv-44f3-qqx6"],"url":"https://o3.security/vulnerability/CVE-2026-34221","summary":"MikroORM has Prototype Pollution in Utils.merge","details":"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.","published":"2026-03-31T15:17:45.286Z","modified":"2026-08-07T11:31:09.128255851Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"@mikro-orm/core","fixedVersion":"6.6.10"},{"ecosystem":"npm","name":"@mikro-orm/core","fixedVersion":"7.0.6"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34221.json"},{"type":"ADVISORY","url":"https://github.com/mikro-orm/mikro-orm/security/advisories/GHSA-qpfv-44f3-qqx6"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-34221"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T11:31:09.128255851Z"}}