23 Oct 2026 15:48:27 UTC
Builder.io Gen2 SDKs through 5.2.11 Prototype Pollution via builder.userAttributes
cve-program · CVE-2026-92781 · Published
CVE-2026-92781
Builder.io Gen2 SDKs through 5.2.11 Prototype Pollution via builder.userAttributes
CVSS 4.0 5.3 MEDIUMCVSS 3.1 6.3 MEDIUMCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-92781
PublishedBuilder.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.
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