CVE-2026-45302 — Prototype Pollution in parse-nested-form-data via `__proto__` in FormData field names
parse-nested-form-data is a tiny node module for parsing FormData by name into objects and arrays. Prior to version 1.0.1, parseFormData() walks bracket and dot-notation FormDat…
Published: 2026-06-01 · CVSS: 8.2 · CVSS 3.1
parse-nested-form-data is a tiny node module for parsing FormData by name into objects and arrays. Prior to version 1.0.1, parseFormData() walks bracket and dot-notation FormData field names into nested objects without filtering reserved property keys. A single FormData field whose name begins with __proto__, or contains .__proto__. mid-path, causes the parser to traverse onto Object.prototype and assign properties there, polluting the prototype chain of every plain object in the running process. This issue has been patched in version 1.0.1.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7