better-auth before 1.4.2 basePath Modification DoS (better-auth better-auth)

CVE-2025-71401
CRITICAL 9.3

At a glance

Source
NVD
EPSS
EPSS 0.46 % · percentile 40 ()
State
PUBLISHED
Published
Updated
Assigner
VulnCheck
NVD status
Deferred

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.

Weaknesses (CWE)

  • CWE-770 — Allocation of Resources Without Limits or Throttling

References

Scores

VersionScoreVectorScored by
CVSS 4.0CRITICAL 9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NVulnCheck
CVSS 3.1MEDIUM 5.9CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HVulnCheck
CVSS 4.0CRITICAL 9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XNVD · disclosure@vulncheck.com (Secondary)
CVSS 3.1MEDIUM 5.9CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HNVD · disclosure@vulncheck.com (Secondary)

Advisories

European references

Affected products

ProductVersions
better-auth · better-authaffected 0 < 1.4.2 ; unaffected 1.4.2

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD