{"id":"CVE-2026-2950","aliases":["GHSA-f23m-r3pf-42rh"],"url":"https://o3.security/vulnerability/CVE-2026-2950","summary":"lodash vulnerable to Prototype Pollution via array path bypass in `_.unset` and `_.omit`","details":"### Impact\n\nThe `_.unset`, `_.omit`, and `_.pullAt` functions are vulnerable to prototype pollution. The fix for [CVE-2025-13465](https://github.com/lodash/lodash/security/advisories/GHSA-xxjr-mmjv-4gpg) only guards against string key members, so an attacker can bypass the check by passing array-wrapped path segments. This allows deletion of properties from built-in prototypes such as `Object.prototype`, `Number.prototype`, and `String.prototype`.\n\nThe issue permits deletion of prototype properties but does not allow overwriting their original behavior.\n\n### Patches\n\nThe issue is patched from 4.18.0 to 4.18.1 depending on the package: `lodash`, `lodash-es`, and `lodash-amd` in 4.18.1, and the standalone `lodash.unset` and `lodash.omit` packages in 4.18.0.\n\n### Workarounds\n\nNone. Upgrade to the patched version.\n\n### References\n\n- [CVE-2025-13465 / GHSA-xxjr-mmjv-4gpg](https://github.com/lodash/lodash/security/advisories/GHSA-xxjr-mmjv-4gpg) (original fix that this bypasses)","published":"2026-03-31T19:18:35.796Z","modified":"2026-10-28T02:31:11.896256232Z","cvss":{"score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L"},"epss":{"score":0.00317,"percentile":0.24746,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"lodash","fixedVersion":"4.18.1"},{"ecosystem":"npm","name":"lodash-es","fixedVersion":"4.18.1"},{"ecosystem":"npm","name":"lodash-amd","fixedVersion":"4.18.1"},{"ecosystem":"npm","name":"lodash.unset","fixedVersion":"4.18.0"},{"ecosystem":"npm","name":"lodash.omit","fixedVersion":"4.18.0"}],"fix":{"url":"https://github.com/lodash/lodash/commit/4f0e376589e1889e8993e212a5c9041112ad178e","label":"lodash/lodash@4f0e376"},"references":[{"type":"ADVISORY","url":"https://cna.openjsf.org/security-advisories.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/2xxx/CVE-2026-2950.json"},{"type":"ADVISORY","url":"https://github.com/lodash/lodash/security/advisories/GHSA-f23m-r3pf-42rh"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-2950"},{"type":"WEB","url":"https://github.com/lodash/lodash/security/advisories/GHSA-xxjr-mmjv-4gpg"},{"type":"WEB","url":"https://github.com/lodash/lodash/commit/4f0e376589e1889e8993e212a5c9041112ad178e"},{"type":"WEB","url":"https://github.com/lodash/lodash/commit/87e6676934f7b4450fad68c35f0325ba165b48f8"},{"type":"WEB","url":"https://github.com/lodash/lodash/commit/bbcf0036d27ef936f175bf26e73e247994d8e1e4"},{"type":"WEB","url":"https://github.com/lodash/lodash/commit/db27b6bb14b12a1451b20edf87dfe307b87a337d"},{"type":"WEB","url":"https://github.com/lodash/lodash/commit/fe8d32eda854377349a4f922ab7655c8e5df9a0b"},{"type":"PACKAGE","url":"https://github.com/lodash/lodash"},{"type":"WEB","url":"https://github.com/lodash/lodash/releases/tag/4.18.1"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-28T02:31:11.896256232Z"}}