CVE-2026-92781

Builder.io Gen2 SDKs through 5.2.11 Prototype Pollution via builder.userAttributes

5.3 Medium

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.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: Passive

What an attacker can affect

Confidentiality: Low
Integrity: Low
Availability: Low

Exploit likelihood

0.36%Up 0.1 points since Sep 17, 2026

What each source reports

CVE List Score used 5.3

Builder.io Gen2 SDKs through 5.2.11 Prototype Pollution via builder.userAttributes

Record: CVE-2026-92781
CVSS 4.0: 5.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
CVSS 3.1: 6.3 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L
Weakness: CWE-1321
Updated: 2026-11-02

EUVDEUVD-2026-81044 5.3

Record: EUVD-2026-81044
CVSS 4.0: 5.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
Updated: 2026-11-02

GitHub AdvisoriesGHSA-mgr8-fxxv-82mj 5.3

Builder.io Gen2 SDKs through versions 5.2.11 and 0.25.13 contain a prototype pollution...

Record: GHSA-mgr8-fxxv-82mj
CVSS 4.0: 5.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1: 6.3 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L
Weakness: CWE-1321
Updated: 2026-11-02

NVD 5.3

Record: CVE-2026-92781
CVSS 4.0: 5.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1: 6.3 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L
Weakness: CWE-1321
Updated: 2026-11-02

Affected products

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	CVE List, EUVD, GitHub Advisories, NVD

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-92781 is a medium vulnerability (CVSS 5.3) in Builderio @builder.io/sdk-angular, published September 16, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.36%, the 29th percentile. No source names a fixed version.