Description
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.
Recommendation
Update the form-data-objectizer package to the latest compatible version. Followings are version details:
- Affected version(s): <= 1.0.0
- Patched version(s): 1.0.1
References
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- @rvf/set-get has a prototype pollution issue that's reachable via @rvf/core preprocessFormData (HTTP form data) - CVE-2026-44483
- scimPatch vulnerable to prototype pollution via unfiltered keys in patch - CVE-2026-48170
- Axios has a Patch Bypass: Proxy-Authorization Header Injection via Prototype Pollution — Incomplete Null-Prototype Fix - CVE-2026-44489
- Axios: XSRF Token Cross-Origin Leakage via Prototype Pollution Gadget in `withXSRFToken` Boolean Coercion - CVE-2026-42042
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See something that needs correcting? Let us knowUpdated June 09, 2026