better-auth oauth-provider up to 1.6.4/1.7.0-beta.1 OAuth Client Creation Endpoint authorization

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability has been found in better-auth oauth-provider up to 1.6.4/1.7.0-beta.1 and classified as problematic. Impacted is an unknown function of the component OAuth Client Creation Endpoint. This manipulation causes authorization. This vulnerability is handled as CVE-2026-41427. The attack can be initiated remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic was found in better-auth oauth-provider up to 1.6.4/1.7.0-beta.1. Affected by this vulnerability is an unknown part of the component OAuth Client Creation Endpoint. The manipulation with an unknown input leads to a authorization vulnerability. The CWE definition for the vulnerability is CWE-863. The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions. As an impact it is known to affect integrity. The summary by CVE is:

Better Auth is an authentication and authorization library for TypeScript. Prior to 1.6.5, the clientPrivileges option documents a create action, but the OAuth client creation endpoints did not invoke the hook before persisting new clients. Deployments that configured clientPrivileges to restrict client registration were not actually restricted — any authenticated user could reach the create endpoints and register an OAuth client with attacker-chosen redirect URIs and metadata. This vulnerability is fixed in 1.6.5.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-41427 since 04/20/2026. The exploitation appears to be easy. The attack can be launched remotely. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 1.6.5 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-25617). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authorization
CWE: CWE-863 / CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: oauth-provider 1.6.5

Timelineinfo

04/20/2026 CVE reserved
04/24/2026 +4 days Advisory disclosed
04/24/2026 +0 days VulDB entry created
05/17/2026 +23 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-41427 (🔒)
GCVE (CVE): GCVE-0-2026-41427
GCVE (VulDB): GCVE-100-359551
EUVD: 🔒

Entryinfo

Created: 04/24/2026 21:57
Updated: 05/17/2026 09:05
Changes: 04/24/2026 21:57 (66), 04/25/2026 00:53 (1), 05/17/2026 09:05 (11)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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