Prototype pollution in form-data-objectizer via bracket-notation form keys_CVE-2026-46510

8.2 / 10

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L

Description

form-data-objectizer converts FormData to object. Prior to 1.0.1, form-data-objectizer walks bracket-notation form keys (e.g. name[sub]) into nested objects without filtering __proto__, constructor, or prototype. A single HTTP form field whose name starts with __proto__[...] causes the library to mutate Object.prototype, which is a prototype pollution primitive of the entire Node.js process. This vulnerability is fixed in 1.0.1.

Basic Information

ID CVE-2026-46510

Source GitHub_M

Published May 29, 2026 at 13:40

Affected Product

Vendor kaspernj

Product form-data-objectizer

Version < 1.0.1

Affected Versions kaspernj form-data-objectizer < 1.0.1

CWE Classification

CWE-1321

References

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    "published": "2026-05-29T13:40:22.772Z",
    "modified": "2026-05-29T13:40:22.772Z",
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