CVE-2025-71399
Routing normalization flaw in Better Auth allows bypass of disabled paths and rate limits.
Is CVE-2025-71399 being exploited?
Not confirmed. CVE-2025-71399 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.31% probability of exploitation in the next 30 days.
How severe is CVE-2025-71399?
CVE-2025-71399 is rated High. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2025-71399?
Yes. A fix has been recorded for CVE-2025-71399. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2025-71399 affect?
CVE-2025-71399 affects Better Auth < 1.4.5, rou3 router library versions that collapse empty segments, Deployments that do not normalize duplicate slashes at proxy/platform. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2025-71399?
Upgrade Better Auth to >=1.4.5 and ensure proxies normalize multiple slashes.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Attackers can bypass disabledPaths and path-based rate limits by sending URLs with extra slashes, enabling unauthorized requests, abuse, or brute-force.
Patch when possible
- affected< 1.4.5
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.