CVE-2026-45337: Better-Auth Better Auth

High severity, CVSS 7.6. EPSS: 0.2% chance of exploitation in the next 30 days.

Better Auth is an authentication and authorization library for TypeScript. From 1.6.0 until 1.6.11, the deviceAuthorization plugin treats any authenticated session as the owner of any pending device code because GET /device does not claim the row and POST /device/approve and POST /device/deny short-circuit when userId is unset, allowing an authenticated attacker who learns a valid user_code to bind the polling device to the attacker's account or deny the legitimate flow. This issue is fixed in version 1.6.11.

Affected products

• Better-Auth Better Auth: from 1.6.0, before 1.6.11 (fixed in 1.6.11)

Published 2026-07-15. Last modified 2026-07-21.