CVE-2026-67333

better-auth before 1.6.13 (and pre-release builds 1.7.0-beta.0 through 1.7.0-beta.3) fail to validate the scheme of redirect_uris registered via the deprecated oidc-provider plugin and the mcp plugin (which wraps the same provider). An attacker can register an OAuth client with a javascript: redirect_uri, which the authorization server later returns unchanged in the consent response. If the deployment's consent page navigates the browser to the returned redirectURI (e.g. assigning it to window.location.href), the attacker's JavaScript executes in the authorization-server origin, exposing the victim's session and enabling account takeover.

CVSS v3 7.2 HIGH

7.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/better-auth/better-auth/security/advisories/GHSA-86j7-9j95-vpqj
https://www.vulncheck.com/advisories/better-auth-before-stored-xss-via-javascript-redirect-uri

Configurations

No configuration.

History

01 Aug 2026, 13:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-08-01 13:17

Updated : 2026-08-01 13:17

NVD link : CVE-2026-67333

Mitre link : CVE-2026-67333

CVE.ORG link : CVE-2026-67333

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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