CVE-2026-110864

Better Auth 1.5.0-beta.12 before 1.7.7 Authentication Bypass via OAuth Proxy

Published Oct 14, 2026 CVSS 4.0 · 9.1 Critical EPSS < 1% KEV · Not listed
Description
Better Auth from 1.5.0-beta.12 before 1.7.7 contains an authentication bypass vulnerability in the OAuth Proxy plugin that allows unauthenticated attackers to sign in as other users by forging encrypted profiles. When the proxy shares the global secret and cookie-stored state is used, attackers can obtain encrypted state for a fake profile with a victim's verified email to take over the account via implicit linking.

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': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Better Auth from 1.5.0-beta.12 before 1.7.7 contains an authentication bypass vulnerability in the OAuth Proxy plugin that allows unauthenticated attackers to sign in as other users by forging encrypted profiles. When the proxy shares the global secret and cookie-stored state is used, attackers can obtain encrypted state for a fake profile with a victim's verified email to take over the account via implicit linking.
Title Better Auth 1.5.0-beta.12 before 1.7.7 Authentication Bypass via OAuth Proxy
First Time appeared Better-auth
Better-auth better Auth
Weaknesses CWE-287
CPEs cpe:2.3:a:better-auth:better_auth:*:*:*:*:*:*:*:*
Vendors & Products Better-auth
Better-auth better Auth
References
Metrics cvssV3_1

{'score': 7.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N'}

cvssV4_0

{'score': 9.1, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Oct 15, 2026, 3:36 PM
Reserved
Oct 14, 2026, 10:18 PM
Status
Deferred
Published
Oct 14, 2026, 11:17 PM
Modified
Oct 16, 2026, 6:25 PM