CVE-2026-46510

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

HIGH
8.2
CVSS Score
Published: May 29, 2026 at 01:40 PM UTC
Updated: July 21, 2026 at 01:39 PM UTC
1 product affected across 1 vendorForm Data Objectizer

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Severity
HIGH8.2
Exploit prediction
EPSS 0.3%
SSVC
PoC

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.0.1
Affected range stops below 1.0.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCPoCAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.2HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
LOW
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-1321

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