{"id":"GHSA-28xv-ph75-77wh","revision":"6540ea068c3e44928da42fe52fb65c33","records":[{"revision":"6540ea068c3e44928da42fe52fb65c33","observedAt":"2026-10-24T13:17:17.793+00:00","statement":{"source":"osv","id":"GHSA-28xv-ph75-77wh","aliases":["CVE-2026-54335"],"title":"Prototype pollution in @feathersjs/commons _.merge via JSON-parsed __proto__","description":"### Impact\n\nThe `_.merge(target, source)` utility exported by `@feathersjs/commons` recursively merges `source` into `target` by iterating `Object.keys(source)`. When `source` was produced by `JSON.parse` and contains a `__proto__` (or `constructor` / `prototype`) key, that key is returned as an own-enumerable property. The recursive merge then resolves `target['__proto__']` to `Object.prototype` and writes the attacker-supplied properties onto it, polluting the prototype for all plain objects in the process for the lifetime of the Node process.\n\n**Scope of real-world risk is limited.** No first-party Feathers package routes input — trusted or untrusted — through `commons._.merge`. The `@feathersjs/authentication` package, which does merge request-influenced data, uses `lodash/merge` (prototype-pollution-safe since 4.17.12), not this utility. Exploitation therefore requires a downstream plugin or application to pass JSON-parsed, attacker-controlled input directly through the exported `_.merge`.\n\n### Patches\n\nFixed in `@feathersjs/commons@5.0.45`. The fix skips `__proto__`, `constructor`, and `prototype` keys during iteration — the standard remediation used by lodash and others.\n\n### Workarounds\n\nAvoid passing JSON-parsed untrusted input through `commons._.merge`. Freezing `Object.prototype` or validating/sanitizing keys upstream also mitigates.\n\n### Credit\n\nReported responsibly by Andrew Ridings (@ridingsa).","state":0,"publishedAt":"2026-07-14T19:40:05+00:00","modifiedAt":"2026-07-14T19:56:45.565577+00:00","affected":[{"ecosystem":"npm","name":"@feathersjs/commons","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"5.0.45"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"LOW"}],"references":["https://github.com/feathersjs/feathers/security/advisories/GHSA-28xv-ph75-77wh","https://github.com/feathersjs/feathers/pull/3690","https://github.com/feathersjs/feathers/commit/28b3c03c63bdbff53115fdaa46c56980e7942acc","https://github.com/feathersjs/feathers","https://github.com/feathersjs/feathers/releases/tag/v5.0.45"],"sourceUrl":"https://github.com/advisories/GHSA-28xv-ph75-77wh","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-28xv-ph75-77wh","identifiers":["GHSA-28xv-ph75-77wh","CVE-2026-54335"]},"retained":false,"historicalAffected":[]}],"coverage":[]}