Description
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.
Published: 2026-06-01
Score: 8.2 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

No vendor fix or workaround currently provided.

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Tracking

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Advisories
Source ID Title
Github GHSA Github GHSA GHSA-xp7r-j8r6-j9h3 parse-nested-form-data has Prototype Pollution via `__proto__` in FormData field names
History

Wed, 03 Jun 2026 02:30:00 +0000

Type Values Removed Values Added
First Time appeared Milamer
Milamer parse-nested-form-data
Vendors & Products Milamer
Milamer parse-nested-form-data

Tue, 02 Jun 2026 15:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 01 Jun 2026 19:00:00 +0000

Type Values Removed Values Added
Description 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.
Title Prototype Pollution in parse-nested-form-data via `__proto__` in FormData field names
Weaknesses CWE-1321
References
Metrics cvssV3_1

{'score': 8.2, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L'}


Subscriptions

Milamer Parse-nested-form-data
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-06-02T14:45:17.644Z

Reserved: 2026-05-11T20:14:43.202Z

Link: CVE-2026-45302

cve-icon Vulnrichment

Updated: 2026-06-02T14:44:14.933Z

cve-icon NVD

Status : Deferred

Published: 2026-06-01T19:16:51.113

Modified: 2026-06-02T16:16:41.663

Link: CVE-2026-45302

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-06-02T20:53:28Z

Weaknesses