{"cve":"CVE-2025-71401","nvd":{"published":"2026-08-02T13:16:52.530","modified":"2026-10-06T22:10:00.247","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.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","score":9.3},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":5.9},"cwes":["CWE-770"],"references":["https://github.com/better-auth/better-auth/security/advisories/GHSA-569q-mpph-wgww","https://www.vulncheck.com/advisories/better-auth-before-basepath-modification-dos"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:47:10.050265369+00:00"},"epss":{"cve":"CVE-2025-71401","score":0.00455,"percentile":0.39251,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-569q-mpph-wgww","url":"https://osv.dev/vulnerability/GHSA-569q-mpph-wgww","summary":"Better Auth affected by external request basePath modification DoS","modified":"2026-09-01T19:02:52.599264581Z","packages":[{"ecosystem":"npm","name":"better-auth","purl":"pkg:npm/better-auth","ranges":["<1.4.2"],"fixed":["1.4.2"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}