CVE-2026-73418
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of service disruption.
- Exploit odds
- 0.9% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.9% in the next 30 days (EPSS).
- Severity: 7.5 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.9% · EPSS, next 30 days
- Weakness
- CWE-20 · Improper input validation
- Record status
- Awaiting Analysis
Attack profile CVSS 3.1 · 7.5
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-73418.md and follow it. Check whether this project is affected by CVE-2026-73418. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- 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
- https://github.com/nextauthjs/next-auth/releases/tag/next-auth%405.0.0-beta.32
- https://github.com/nextauthjs/next-auth/security/advisories/GHSA-xmf8-cvqr-rfgj
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
- https://github.com/nextauthjs/next-auth/releases/tag/next-auth%405.0.0-beta.32
- https://github.com/nextauthjs/next-auth/security/advisories/GHSA-xmf8-cvqr-rfgj