CVE-2026-67335

Published: Aug 1, 2026Modified: Sep 8, 2026Deferred

6.0

Vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:N/VI:H/VA:N/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:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:N/VI:H/VA:N/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:XShow less

Source: disclosure@vulncheck.com (Secondary)

Description

better-auth versions before 1.6.2 fail to validate the OAuth state parameter against the stored nonce when using cookie-backed state storage without PKCE. Attackers can forge the state parameter and supply an attacker-controlled authorization code to create authenticated sessions bound to the attacker's external identity or persistently link attacker accounts to victim profiles.

Related CWEs

CWE-287

Improper Authentication

When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

References (2)

https://github.com/better-auth/better-auth/security/advisories/GHSA-wxw3-q3m9-c3jr

Source: disclosure@vulncheck.com

https://www.vulncheck.com/advisories/better-auth-before-oauth-state-validation-bypass

Source: disclosure@vulncheck.com

Timeline

No history available yet.