CVE-2026-46510 PUBLISHED

Prototype pollution in form-data-objectizer via bracket-notation form keys

Assigner: GitHub_M
Reserved: 14.05.2026 Published: 29.05.2026 Updated: 29.05.2026

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.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L
CVSS Score: 8.2

Product Status

Vendor kaspernj
Product form-data-objectizer
Versions
  • Version < 1.0.1 is affected

References

Problem Types

  • CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') CWE