{"id":"CVE-2021-26707","aliases":["EUVD-2021-1394","GHSA-r6rj-9ch6-g264","ROOT-APP-NPM-CVE-2021-26707"],"status":"published","title":"Prototype pollution in Merge-deep","description":"The merge-deep library before 3.0.3 for Node.js can be tricked into overwriting properties of Object.prototype or adding new properties to it. These properties are then inherited by every object in the program, thus facilitating prototype-pollution attacks against applications using this library.","severity":{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-11","score":0.01917,"percentile":0.80144,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-1321"],"published":"2021-06-02T14:24:30Z","modified":"2026-10-20T10:54:34Z","fixes":[{"ecosystem":"npm","package":"merge-deep","fixed_in":["3.0.3"],"sources":["ghsa","osv"]},{"ecosystem":"Root:npm","package":"merge-deep","fixed_in":["3.0.2-aikido.1"],"sources":["osv"]},{"ecosystem":"Root:npm","package":"@rootio/merge-deep","fixed_in":["3.0.2-root.io.1"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"merge-deep","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.0.3"}]}]},{"source":"osv","ecosystem":"npm","package":"merge-deep","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"3.0.3"}]}]},{"source":"osv","ecosystem":"Root:npm","package":"merge-deep","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.0.2-aikido.1"}]}]},{"source":"osv","ecosystem":"Root:npm","package":"@rootio/merge-deep","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.0.2-root.io.1"}]}]}],"products":[{"vendor":"merge-deep_project","product":"merge-deep"},{"vendor":"netapp","product":"e-series_performance_analyzer"}],"references":[{"url":"https://www.npmjs.com/package/merge-deep","tags":["x_refsource_MISC","x_transferred","Product","Third Party Advisory","advisory","web"]},{"url":"https://github.com/jonschlinkert/merge-deep/commit/11e5dd56de8a6aed0b1ed022089dbce6968d82a5","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://securitylab.github.com/advisories/GHSL-2020-160-merge-deep/","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","advisory"]},{"url":"https://security.netapp.com/advisory/ntap-20210716-0008/","tags":["x_refsource_CONFIRM","x_transferred","Third Party Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-26707","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-r6rj-9ch6-g264"},{"url":"https://security.netapp.com/advisory/ntap-20210716-0008","tags":["web"]},{"url":"https://securitylab.github.com/advisories/GHSL-2020-160-merge-deep","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2021-26707","description":"The merge-deep library before 3.0.3 for Node.js can be tricked into overwriting properties of Object.prototype or adding new properties to it. These properties are then inherited by every object in the program, thus facilitating prototype-pollution attacks against applications using this library.","status":"published","published":"2021-06-02T14:24:30Z","modified":"2024-08-03T20:33:40.345Z","updated_at":"2026-11-02T14:32:57.368269Z"}],"euvd":[{"id":"EUVD-2021-1394","description":"The merge-deep library before 3.0.3 for Node.js can be tricked into overwriting properties of Object.prototype or adding new properties to it. These properties are then inherited by every object in the program, thus facilitating prototype-pollution attacks against applications using this library.","status":"published","published":"2021-06-02T14:24:30Z","modified":"2024-08-03T20:33:40Z","updated_at":"2026-11-03T03:24:50.84326Z"}],"ghsa":[{"id":"GHSA-r6rj-9ch6-g264","title":"Prototype pollution in Merge-deep","description":"The merge-deep library before 3.0.3 for Node.js can be tricked into overwriting properties of Object.prototype or adding new properties to it. These properties are then inherited by every object in the program, thus facilitating prototype-pollution attacks against applications using this library.","status":"published","published":"2021-06-07T22:09:26Z","modified":"2023-11-29T20:52:31Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-1321"],"updated_at":"2026-11-02T14:37:23.843848Z"}],"nvd":[{"id":"CVE-2021-26707","description":"The merge-deep library before 3.0.3 for Node.js can be tricked into overwriting properties of Object.prototype or adding new properties to it. These properties are then inherited by every object in the program, thus facilitating prototype-pollution attacks against applications using this library.","status":"published","published":"2021-06-02T15:15:07.787Z","modified":"2026-06-17T03:43:41.69Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"},{"version":"2.0","score":7.5,"vector":"AV:N/AC:L/Au:N/C:P/I:P/A:P","level":"high","assessor":"primary"}],"cwes":["CWE-1321"],"updated_at":"2026-11-02T14:06:53.987491Z"}],"osv":[{"id":"CVE-2021-26707","description":"The merge-deep library before 3.0.3 for Node.js can be tricked into overwriting properties of Object.prototype or adding new properties to it. These properties are then inherited by every object in the program, thus facilitating prototype-pollution attacks against applications using this library.","status":"published","published":"2021-06-02T15:15:07.787Z","modified":"2026-10-20T10:54:34.443307808Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T15:44:18.778776Z"},{"id":"GHSA-r6rj-9ch6-g264","title":"Prototype pollution in Merge-deep","description":"The merge-deep library before 3.0.3 for Node.js can be tricked into overwriting properties of Object.prototype or adding new properties to it. These properties are then inherited by every object in the program, thus facilitating prototype-pollution attacks against applications using this library.","status":"published","published":"2021-06-07T22:09:26Z","modified":"2023-11-08T04:05:22.158205Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-1321"],"updated_at":"2026-11-02T15:46:55.480549Z"},{"id":"ROOT-APP-NPM-CVE-2021-26707","title":"CVE-2021-26707 in merge-deep - Patched by Root","description":"Root has patched CVE-2021-26707 in the merge-deep package for Root:npm. Multiple fixed versions available.","status":"published","published":"2026-08-28T05:12:56Z","modified":"2026-08-28T06:30:03.007877559Z","updated_at":"2026-11-02T15:53:27.362922Z"}]}}