CVE-2025-27143
CVE-2025-27143 · Beter Auth has an Open Redirect via Scheme-Less Callback Parameter
This page contains facts from public vulnerability sources. Check the original advisory before updating.
Better Auth is an authentication and authorization library for TypeScript. Prior to version 1.1.21, the application is vulnerable to an open redirect due to improper validation of the callbackURL parameter in the email verification endpoint and any other endpoint that accepts callback url. While the server blocks fully qualified URLs, it incorrectly allows scheme-less URLs. This results in the browser interpreting the URL as a fully qualified URL, leading to unintended redirection. An attacker can exploit this flaw by crafting a malicious verification link and tricking users into clicking it. Upon successful email verification, the user will be automatically redirected to the attacker's website, which can be used for phishing, malware distribution, or stealing sensitive authentication tokens. This CVE is a bypass of the fix for GHSA-8jhw-6pjj-8723/CVE-2024-56734. Version 1.1.21 contains an updated patch.
CVSS 6.9 · Medium · EPSS 0.4% · Fix available
- Published
- Updated
Stack: node
Affected products and versions
better-auth
- Versions
- < 1.1.20: Affected
No fix published
better-auth npm
- Affected ranges
- SEMVER: < 1.1.20
Update to 1.1.20
Original sources
- https://github.com/better-auth/better-auth/security/advisories/GHSA-hjpm-7mrm-26w8
- https://github.com/better-auth/better-auth/security/advisories/GHSA-8jhw-6pjj-8723
- https://github.com/better-auth/better-auth/commit/24659aefc35a536b95ea4e5347e52c8803910153
- https://github.com/better-auth/better-auth/commit/b381cac7aafd6aa53ef78b6ab771ebfa24643c80
- https://github.com/better-auth/better-auth/releases/tag/v1.1.21
- https://nvd.nist.gov/vuln/detail/CVE-2025-27143