CVE-2025-71401
better-auth before 1.4.1 basePath Modification DoS
CVSS Score
5.9
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-770 |
| Vendor | better-auth |
| Product | better-auth |
| Published | Aug 2, 2026 |
| Last Updated | Aug 2, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
better-auth / better-auth
0 < 1.4.1
References
Credits
🔍 goksan