{"id":"CVE-2026-48795","aliases":["GHSA-qcm7-3vpr-hj5h"],"url":"https://o3.security/vulnerability/CVE-2026-48795","summary":"Incomplete fix for CVE-2026-25754 in @adonisjs/bodyparser","details":"### Summary\n\nThe fix for [GHSA-f5x2-vj4h-vg4c](https://github.com/adonisjs/core/security/advisories/GHSA-f5x2-vj4h-vg4c) / CVE-2026-25754 introduced in commit [`40e1c71`](https://github.com/adonisjs/bodyparser/commit/40e1c71f958cffb74f6b91bed6630dca979062ed) is incomplete and can be bypassed through nested prototype pollution payloads.\n\nThe original patch replaced the internal `FormFields` storage object with `Object.create(null)`, preventing direct payloads such as `__proto__.polluted`. However, payloads containing a non-dangerous segment before `__proto__` or `constructor.prototype`, such as `user.__proto__.polluted`, still lead to `Object.prototype` pollution.\n\nThis issue is exploitable remotely through a single unauthenticated `multipart/form-data` request using the default configuration.\n\n### Affected versions\n\n- `>= 10.1.3 < 10.1.5`\n- `>= 11.0.0-next.9 < 11.0.3`\n\n### Details\n\nThe regression tests added by the original fix only covered direct payloads such as:\n\n- `__proto__.polluted`\n- `constructor.prototype.polluted`\n\nThese payloads are blocked because the root object no longer inherits from `Object.prototype`.\n\nHowever, lodash `_.set()` (via `@poppinss/utils`) still creates intermediate objects using plain `{}` values. Once a normal segment is encountered, subsequent `__proto__` or `constructor.prototype` segments regain access to `Object.prototype`.\n\n### Impact\n\nAn unauthenticated attacker can remotely pollute `Object.prototype` on any route accepting multipart/form-data requests behind `BodyParserMiddleware`.\n\nBecause the pollution is process-wide, the impact may include authorization bypasses, unexpected behavior in downstream libraries, or prototype pollution gadget chains leading to remote code execution.\n\n### Patches\n\nFixes targeting v6 and v7 have been published below.\n\nUsers should upgrade to a version that includes the following fix:\n\n- https://github.com/adonisjs/bodyparser/releases/tag/v10.1.5\n- https://github.com/adonisjs/bodyparser/releases/tag/v11.0.3\n\n### References\n\n- [CWE-1321](https://cwe.mitre.org/data/definitions/1321.html)\n- Prior advisory this bypasses: [GHSA-f5x2-vj4h-vg4c](https://github.com/adonisjs/core/security/advisories/GHSA-f5x2-vj4h-vg4c) / CVE-2026-25754","published":"2026-07-15T21:23:14.393Z","modified":"2026-08-12T03:51:13.377988080Z","cvss":{"score":8.6,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H"},"epss":{"score":0.00547,"percentile":0.44524,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"@adonisjs/bodyparser","fixedVersion":"10.1.5"},{"ecosystem":"npm","name":"@adonisjs/bodyparser","fixedVersion":"11.0.3"}],"fix":{"url":"https://github.com/adonisjs/bodyparser/commit/8a85eb0c2061b0caca10faedbfc2cf24b56cf9f6","label":"adonisjs/bodyparser@8a85eb0"},"references":[{"type":"WEB","url":"https://github.com/adonisjs/bodyparser/releases/tag/v10.1.5"},{"type":"WEB","url":"https://github.com/adonisjs/bodyparser/releases/tag/v11.0.3"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48795.json"},{"type":"ADVISORY","url":"https://github.com/adonisjs/core/security/advisories/GHSA-qcm7-3vpr-hj5h"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-48795"},{"type":"FIX","url":"https://github.com/adonisjs/bodyparser/commit/8a85eb0c2061b0caca10faedbfc2cf24b56cf9f6"},{"type":"FIX","url":"https://github.com/adonisjs/bodyparser/commit/aa96908f7b3f64c19e15d2d2d916b69137bdf469"},{"type":"WEB","url":"https://github.com/adonisjs/core/security/advisories/GHSA-f5x2-vj4h-vg4c"},{"type":"WEB","url":"https://github.com/adonisjs/bodyparser/commit/40e1c71f958cffb74f6b91bed6630dca979062ed"},{"type":"PACKAGE","url":"https://github.com/adonisjs/core"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:13.377988080Z"}}