CVE-2026-45302
Prototype Pollution in parse-nested-form-data via `__proto__` in FormData field names
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.
INFO
Published Date :
June 1, 2026, 7:16 p.m.
Last Modified :
July 22, 2026, 8:10 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-45302
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update the parse-nested-form-data dependency to 1.0.1.
- Verify that prototype pollution is no longer possible.
- Remove any custom prototype pollution checks.
- Deploy the updated application.
Public PoC/Exploit Available at Github
CVE-2026-45302 has a 2 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-45302.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-45302 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-45302
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Vulnerability disclosures and root-cause analysis. 10 published CVEs across npm and WordPress: prototype pollution, broken access control, unauthenticated upload to RCE, and SSRF.
appsec cve prototype-pollution responsible-disclosure security vulnerability-research
None
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-45302 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-45302 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Translated by [email protected]
Jul. 22, 2026
Action Type Old Value New Value Added Translation Title: parse-nested-form-data de milamer, Description: parse-nested-form-data es un pequeño módulo de Node para analizar datos de FormData por nombre en objetos y arrays. Antes de la versión 1.0.1, parseFormData() recorre los nombres de campo de FormData con notación de corchetes y de puntos en objetos anidados sin filtrar las claves de propiedades reservadas. Un único campo de FormData cuyo nombre comienza con __proto__, o contiene .__proto__. a mitad de ruta, hace que el analizador recorra Object.prototype y asigne propiedades allí, contaminando la cadena de prototipos de cada objeto plano en el proceso en ejecución. Este problema ha sido parcheado en la versión 1.0.1. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'milamer', 'product': 'parse-nested-form-data', 'versions': [{'status': 'affected', 'version': '< 1.0.1'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-45302', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-02T14:44:56.480694Z'} -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 02, 2026
Action Type Old Value New Value Added Reference https://github.com/milamer/parse-nested-form-data/security/advisories/GHSA-xp7r-j8r6-j9h3 -
New CVE Received by [email protected]
Jun. 01, 2026
Action Type Old Value New Value 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L Added CWE CWE-1321 Added Reference https://github.com/milamer/parse-nested-form-data/commit/527ad58eb486e32438f7198fb88315c20449d792 Added Reference https://github.com/milamer/parse-nested-form-data/releases/tag/v1.0.1 Added Reference https://github.com/milamer/parse-nested-form-data/security/advisories/GHSA-xp7r-j8r6-j9h3