CVE-2026-121802

Unauthenticated State Signing Allows Account Email Changes

Published Nov 4, 2026 CVSS 3.1 · 9.1 Critical EPSS < 1% KEV · Not listed
Description
@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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Title Unauthenticated State Signing Allows Account Email Changes
Type Values Removed Values Added
First Time appeared Better-auth
Better-auth better Auth
CPEs cpe:2.3:a:better-auth:better_auth:*:*:*:*:*:*:*:*
Vendors & Products Better-auth
Better-auth better Auth
Type Values Removed Values Added
Description @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.
Weaknesses CWE-346
References
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Nov 6, 2026, 6:45 PM
Reserved
Nov 4, 2026, 2:36 AM
Status
Deferred
Published
Nov 4, 2026, 3:17 AM
Modified
Nov 6, 2026, 7:17 PM