CVE-2026-40155

The Auth0 Next.js SDK is a library for implementing user authentication in Next.js applications. In versions 4.12.0 through 4.17.1, simultaneous requests that trigger a nonce retry may cause the proxy cache fetcher to perform improper lookups for the token request results. Users are affected if their project uses both the vulnerable versions and the proxy handler /me/* and /my-org/* with DPoP enabled. This issue has been fixed in version 4.18.0.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/auth0/nextjs-auth0/commit/98c36dc306970c2230ea1a32efef431d29b99978	Patch
https://github.com/auth0/nextjs-auth0/releases/tag/v4.18.0	Product Release Notes
https://github.com/auth0/nextjs-auth0/security/advisories/GHSA-xq8m-7c5p-c2r6	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:auth0:nextjs-auth0:*:*:*:*:*:node.js:*:*

History

No history.

Information

Published : 2026-04-17 21:16

Updated : 2026-06-17 10:44

NVD link : CVE-2026-40155

Mitre link : CVE-2026-40155

CVE.ORG link : CVE-2026-40155

JSON object : View

Products Affected

auth0

nextjs-auth0

CWE

CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CWE-863

Incorrect Authorization

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