Vulnerability record/PUBLISHED/Published Nov 4, 2026 02:36:13 UTC

CVE-2026-121802

@better-auth/expo before 1.7.16 allows certain account-takeover outcomes (e.g., unauthenticated changes of any account's email address), because it signs a caller-supplied state value without checking whether that value had been issued by the server. NOTE: the application secret must be rotated after updating to a fixed version.

Base score9.1/ 10

SeverityCriticalCVSS 3.1

Exploitability / impact

CVSS metric breakdown

Vector-derived attributes

Base severityCritical

Attack vectorNetworkAV

Attack complexityLowAC

Privileges requiredNonePR

User interactionNoneUI

ScopeUnchangedS

Confidentiality impactHighC

Integrity impactHighI

Availability impactNoneA

CVSS vector stringCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS communicates standardized severity and impact characteristics. It does not establish whether a system is exploitable in your specific environment.

Record context

CVE Numbering Authoritymitre

Last updatedNov 4, 2026 02:44:07 UTC

PublishedNov 4, 2026 02:36:13 UTC

ReservedNov 4, 2026 02:36:12 UTC