CVE-2023-48309

What it is

NextAuth.js provides authentication for Next.js. `next-auth` applications prior to version 4.24.5 that rely on the default Middleware authorization are affected by a vulnerability. A bad actor could create an empty/mock user, by getting hold of a NextAuth.js-issued JWT from an interrupted OAuth sign-in flow (state, PKCE or nonce). Manually overriding the `next-auth.session-token` cookie value with this non-related JWT would let the user simulate a logged in user, albeit having no user information associated with it. (The only property on this user is an opaque randomly generated string). This vulnerability does not give access to other users' data, neither to resources that require proper authorization via scopes or other means. The created mock user has no information associated with it (ie. no name, email, access_token, etc.) This vulnerability can be exploited by bad actors to peek at logged in user states (e.g. dashboard layout). `next-auth` `v4.24.5` contains a patch for the vulnerability. As a workaround, using a custom authorization callback for Middleware, developers can manually do a basic authentication.

At a glance

Exploitability

Can be exploited over the network without logging in. Limited direct impact.

Exploit odds

0.7% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2023-11-20 19:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 06:33 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.7% in the next 30 days (EPSS).
• Severity: 5.3 MEDIUM (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2023-11-20 19:15 UTC

Last modified

2026-06-17 06:33 UTC

Exploit probability

0.7% · EPSS, next 30 days

Weakness

CWE-285

Record status

Modified

Affected

• nextauth.js next-auth < 4.24.5

Attack profile CVSS 3.1 · 5.3

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

None

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-2023-48309.md and follow it. Check whether this project is affected by CVE-2023-48309. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

Copy as ticket · More options · Status badge