Next Auth

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.

Published: 2026-08-12T20:21:11.318Z
Updated: 2026-08-13T12:53:44.683Z

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, Auth.js stores the OAuth/OIDC anti-CSRF checks state, nonce, and the PKCE verifier in global cookies that are not bound to the provider that created them. On callback, a check value minted during a sign-in started with one provider can satisfy the callback for a different provider because the stored cookie is not verified against the callback provider's identity, including the provider ID, issuer, client ID, or redirect URI. In a multi-provider application that permits account linking while logged in, when one provider's authorization request is observable and a target provider callback can be satisfied without a PKCE verifier, an attacker can lure a victim into starting a legitimate same-origin flow and link the attacker's target-provider account to the victim's Auth.js user. The linked provider grants the attacker persistent sign-in to the victim's account, while cross-site request forgery alone is insufficient. This issue is fixed in @auth/core 0.41.3 and next-auth 4.24.15 and 5.0.0-beta.32.

Published: 2026-08-12T20:23:39.174Z
Updated: 2026-08-13T15:32:15.689Z

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.

Published: 2023-11-20T18:25:01.896Z
Updated: 2024-08-29T13:41:03.796Z

NextAuth.js is an open source authentication solution for Next.js applications. `next-auth` applications using OAuth provider versions before `v4.20.1` have been found to be subject to an authentication vulnerability. A bad actor who can read traffic on the victim's network or who is able to social engineer the victim to click a manipulated login link could intercept and tamper with the authorization URL to **log in as the victim**, bypassing the CSRF protection. This is due to a partial failure during a compromised OAuth session where a session code is erroneously generated. This issue has been addressed in version 4.20.1. Users are advised to upgrade. Users unable to upgrade may using Advanced Initialization, manually check the callback request for state, pkce, and nonce against the provider configuration to prevent this issue. See the linked GHSA for details.

Published: 2023-03-09T20:37:11.407Z
Updated: 2025-02-25T14:59:02.632Z

`@next-auth/upstash-redis-adapter` is the Upstash Redis adapter for NextAuth.js, which provides authentication for Next.js. Applications that use `next-auth` Email Provider and `@next-auth/upstash-redis-adapter` before v3.0.2 are affected by this vulnerability. The Upstash Redis adapter implementation did not check for both the identifier (email) and the token, but only checking for the identifier when verifying the token in the email callback flow. An attacker who knows about the victim's email could easily sign in as the victim, given the attacker also knows about the verification token's expired duration. The vulnerability is patched in v3.0.2. A workaround is available. Using Advanced Initialization, developers can check the requests and compare the query's token and identifier before proceeding.

Published: 2022-09-28T21:05:09.000Z
Updated: 2025-04-23T16:54:22.841Z