{"cve":"CVE-2026-73418","nvd":{"published":"2026-08-12T21:17:40.890","modified":"2026-09-09T20:58:37.713","status":"Awaiting Analysis","description":"NextAuth.js provides authentication for Next.js. Prior to @auth/core 0.41.3 and next-auth 4.24.15 and 5.0.0-beta.32, the exported getToken() helper in the next-auth/jwt and @auth/core/jwt modules can throw an uncaught exception when it reads a malformed Authorization: Bearer header. When no session cookie is present, getToken() URL-decodes the bearer value before validating it, and malformed percent encoding causes decodeURIComponent() to throw instead of treating the token as invalid. Because getToken() is commonly called in API routes, middleware, and server-side request handlers, a single unauthenticated request can trigger an unhandled exception in code paths that authenticate requests, causing a per-request denial of service without exposing tokens, sessions, or other data and without bypassing authentication. This issue is fixed in @auth/core 0.41.3 and next-auth 4.24.15 and 5.0.0-beta.32.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-20","CWE-248"],"references":["https://github.com/nextauthjs/next-auth/commit/5bca2399a79ba8d116ca5179b4b1ebcd152e7f05","https://github.com/nextauthjs/next-auth/commit/e707770f00c52b3479e43422b0200b059149ed53","https://github.com/nextauthjs/next-auth/pull/13469","https://github.com/nextauthjs/next-auth/releases/tag/%40auth%2Fcore%400.41.3","https://github.com/nextauthjs/next-auth/releases/tag/next-auth%404.24.15"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:48:17.459049833+00:00"},"epss":{"cve":"CVE-2026-73418","score":0.00877,"percentile":0.59042,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-xmf8-cvqr-rfgj","url":"https://osv.dev/vulnerability/GHSA-xmf8-cvqr-rfgj","summary":"Auth.js: getToken() throws an uncaught exception on malformed Bearer authorization headers","modified":"2026-09-10T03:51:12.549867672Z","packages":[{"ecosystem":"npm","name":"@auth/core","purl":"pkg:npm/%40auth/core","ranges":[">=0.1.0 <0.41.3"],"fixed":["0.41.3"]},{"ecosystem":"npm","name":"next-auth","purl":"pkg:npm/next-auth","ranges":[">=5.0.0-beta.0 <5.0.0-beta.32"],"fixed":["5.0.0-beta.32"]},{"ecosystem":"npm","name":"next-auth","purl":"pkg:npm/next-auth","ranges":[">=4.0.6 <4.24.15"],"fixed":["4.24.15"]}]}],"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."]}