Improper Authentication Affecting better-auth package, versions >=1.5.0-beta.12 <1.7.7
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published18 Oct 2026
- disclosed15 Oct 2026
- creditiabdullah215, martinfrancois
Introduced: 15 Oct 2026
NewCVE-2026-110864 (opens in a new tab)How to fix?
Upgrade better-auth to version 1.7.7 or higher.
Overview
better-auth is a The most comprehensive authentication library for TypeScript.
Affected versions of this package are vulnerable to Improper Authentication via cross-purpose reuse of verification records, where a token issued for one authentication flow (such as OAuth state or OAuth proxy) can be submitted to the magic-link verification endpoint to obtain a session. The magic-link handler previously looked up verification records by the raw stored token without a type discriminator, allowing an attacker who possesses a valid token from a different flow to authenticate as the associated user. The fix introduces purpose-scoped identifiers (prefixed with magic-link:) and a strict record schema check that rejects records not carrying type: "magic-link", and derives per-purpose encryption keys for OAuth flows using HKDF to prevent ciphertext reuse across contexts.