CVE-2026-92781
MEDIUMCVSS 6.3Description
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.
Timeline
Published:September 16th, 2026 9:17 PM
Last modified:September 24th, 2026 9:08 PM
CVSS Scoring
CVSS v3: 6.3 (MEDIUM)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L
Weaknesses (CWE)
References & Reports
Advisories, patches, and third-party reports
- 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
Source: NIST NVD · Data may lag official sources by up to one minute