CVE-2025-71399

Better Auth relies on better-call, which uses the rou3 router library. In affected versions of rou3, paths are normalized by removing empty segments, so /path, //path, and ///path resolve to the same route. In Better Auth versions prior to 1.4.5 (which bundles the fixed rou3), this can allow attackers to bypass disabledPaths configuration and path-based rate limits by submitting requests with extra slashes in the URL path. The issue does not apply in deployments where the proxy or platform normalizes URLs by collapsing multiple slashes.

CVSS v3 8.6 HIGH

8.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/better-auth/better-auth/commit/f60b43fa648399534507c9ac7db36d705b8874c3
https://github.com/better-auth/better-auth/security/advisories/GHSA-x732-6j76-qmhm
https://www.vulncheck.com/advisories/better-auth-before-path-normalization-bypass-via-rou3

Configurations

No configuration.

History

02 Aug 2026, 13:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-08-02 13:16

Updated : 2026-08-03 17:16

NVD link : CVE-2025-71399

Mitre link : CVE-2025-71399

CVE.ORG link : CVE-2025-71399

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

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