Review reviewHigh

CVE-2026-45337

better-auth better-auth, better auth

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.

CVSS: 7.6
EPSS: 0.14%
CISA KEV: Not listed
Published: 2026.07.16

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.14%

Technical severityCVSS 7.6

Vulnerability overview

Affected product and versions

Product: better-auth better-auth, better auth
Affected versions: >= >= 1.6.0, < 1.6.11, >= 1.6.0 < 1.6.11
Fixed versions: 1.6.11

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that better-auth better-auth, better auth and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:L
CWE: CWE-285, CWE-345