CVE-2026-92781

Builder.io Gen2 SDKs through versions 5.2.11 and 0.25.13 contain a prototype pollution vulnerability in the unflatten helper that processes builder.userAttributes query parameters without prototype guards. Attackers can craft preview links with __proto__ or prototype segments to pollute Object.prototype in a visitor's browser when the SDK processes the malicious URL.

CVSS v3 6.3 MEDIUM

6.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/BuilderIO/builder
https://github.com/BuilderIO/builder/blob/main/packages/sdks/src/functions/get-content/generate-content-url.ts
https://github.com/BuilderIO/builder/blob/main/packages/sdks/src/helpers/flatten.ts#L60-L76
https://github.com/BuilderIO/builder/issues/4824
https://www.vulncheck.com/advisories/builder-io-gen2-sdks-through-5.2.11-prototype-pollution-via-builder-userattributes
https://github.com/BuilderIO/builder/issues/4824

Configurations

No configuration.

History

21 Sep 2026, 16:17

Type	Values Removed	Values Added
References	~~() https://github.com/BuilderIO/builder/issues/4824 -~~	() https://github.com/BuilderIO/builder/issues/4824 -

16 Sep 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-16 21:17

Updated : 2026-09-24 21:08

NVD link : CVE-2026-92781

Mitre link : CVE-2026-92781

CVE.ORG link : CVE-2026-92781

JSON object : View

Products Affected

No product.

CWE

CWE-1321

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

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