CVE-2025-71401

Description

better-auth (npm) before 1.4.2 allows an external request to configure baseURL when it is not otherwise defined (e.g., BETTER_AUTH_URL is unset). An attacker able to make the very first request to the server after startup can poison the router's base path, causing all routes to return 404 for all users (denial of service). The issue is not reachable when baseURL is explicitly configured or on typical managed hosting platforms.

References

https://www.vulncheck.com/advisories/better-auth-before-basepath-modification-dos

https://github.com/better-auth/better-auth/security/advisories/GHSA-569q-mpph-wgww

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3

CVSS v4