CVE-2025-71399 (GCVE-0-2025-71399)
Vulnerability from cvelistv5 – Published: 2026-08-02 12:15 – Updated: 2026-10-08 15:21
VLAI
EPSS
VEX
Title
Better Auth before 1.4.5 Path Normalization Bypass via rou3
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-03 15:48 UTC
CWE
- CWE-20 - Improper Input Validation
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/better-auth/better-auth/securi… | vendor-advisory |
| https://github.com/better-auth/better-auth/commit… | patch |
| https://www.vulncheck.com/advisories/better-auth-… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| better-auth | better-auth |
Affected:
0 , < 1.4.5
(semver)
Unaffected: 1.4.5 (semver) cpe:2.3:a:better-auth:better-auth\/oauth-provider:*:*:*:*:*:node.js:*:* |
Date Public
2025-12-15 00:00
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