CVE-2026-40155

EUVD-2026-23537

17.04.2026, 21:16

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.

Race Condition

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	Primary	5.4 MEDIUM	NETWORK	HIGH	LOW	CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:L/A:N

Awaiting analysis

This vulnerability is currently awaiting analysis.

Base Score

CVSS 3.x

EPSS Score

Percentile: Unknown

Common Weakness Enumeration

CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
The program contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently.

References

https://github.com/auth0/nextjs-auth0/commit/98c36dc306970c2230ea1a32efef431d29b99978

https://github.com/auth0/nextjs-auth0/releases/tag/v4.18.0

https://github.com/auth0/nextjs-auth0/security/advisories/GHSA-xq8m-7c5p-c2r6