CVE-2026-53516 json
Better Auth: Account takeover via OAuth auto-link to unverified pre-registered email
published 5mo ago modified last mo. also EUVD-2026-44732 , GHSA-g38m-r43w-p2q7
- cvss
- 8.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 21%
- public exploits
- 0
- none known
Summary
Better Auth is an authentication and authorization library for TypeScript. Prior to 1.6.11, Better Auth's OAuth callback auto-link gate in handleOAuthUserInfo accepts implicit account linking when the OAuth provider asserts email_verified: true without requiring the local user row's emailVerified field to also be true, allowing an attacker who pre-registers a victim email through /sign-up/email to bind the victim's OAuth identity to the attacker's account. The same primitive affects one-tap, and emailAndPassword.requireEmailVerification: true does not mitigate the link-time verification change. This issue is fixed in version 1.6.11.
Patch / fix
- npm better-auth 1.6.11
- better-auth better_auth 1.6.11
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 3mo ago
Exploit prediction
0.29% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L |
| GitHub | 3.1 | 8.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | better-auth | <1.6.11 |
1.6.11 |
Affected products
- better-auth better-auth
Classification
References
-
github.com
/better-auth/better-auth/pull/9578
web, issue-tracking, patch
-
github.com
/better-auth/better-auth/commit/da7e50beee849c59a2ed1ec6b3a38cc6ab9fb563
web, patch
-
github.com
/better-auth/better-auth/security/advisories/GHSA-g38m-r43w-p2q7
web, mitigation, vendor-advisory, advisory
-
github.com
/better-auth/better-auth/releases/tag/v1.6.11
web, release-notes
-
nvd.nist.gov
/vuln/detail/CVE-2026-53516
advisory
-
github.com
/better-auth/better-auth
package
Sources
- CVE List CVE-2026-53516
- GitHub Advisory GHSA-g38m-r43w-p2q7
- NVD CVE-2026-53516
- Maintainer advisory GHSA-g38m-r43w-p2q7
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of better-auth/better-auth published their own advisory on GitHub. Reviewed sources take precedence over it.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.