joi before versions 17.13.8 and 18.2.9 contains a prototype pollution vulnerability in the messages compilation function that accepts __proto__ as an error code. Attackers can supply __proto__ keys in custom messages to replace the returned object's prototype, breaking downstream code relying on Object.prototype methods.
History

Wed, 16 Sep 2026 14:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 15 Sep 2026 12:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-915
References
Metrics threat_severity

None

threat_severity

Moderate


Sun, 13 Sep 2026 14:00:00 +0000

Type Values Removed Values Added
First Time appeared Hapijs
Hapijs joi
Vendors & Products Hapijs
Hapijs joi

Sun, 13 Sep 2026 11:00:00 +0000

Type Values Removed Values Added
Description joi before versions 17.13.8 and 18.2.9 contains a prototype pollution vulnerability in the messages compilation function that accepts __proto__ as an error code. Attackers can supply __proto__ keys in custom messages to replace the returned object's prototype, breaking downstream code relying on Object.prototype methods.
Title joi before 17.13.8 and 18.2.9 Prototype Pollution via messages
Weaknesses CWE-1321
References
Metrics cvssV3_1

{'score': 3.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N'}

cvssV4_0

{'score': 6.3, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published: 2026-09-13T10:45:42.498Z

Updated: 2026-09-24T14:21:52.339Z

Reserved: 2026-09-13T10:14:57.680Z

Link: CVE-2026-90771

cve-icon Vulnrichment

Updated: 2026-09-16T14:03:13.405Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-09-13T11:17:01.613

Modified: 2026-09-24T20:44:42.207

Link: CVE-2026-90771

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-09-13T10:45:42Z

Links: CVE-2026-90771 - Bugzilla