CVE-2026-40155: Auth0 Next.js SDK has Improper Proxy Cache Lookup

April 21, 2026

In affected versions of the Next.js SDK, simultaneous requests that trigger a nonce retry may cause the proxy cache fetcher to perform improper lookups for the token request results.

References

github.com/advisories/GHSA-xq8m-7c5p-c2r6
github.com/auth0/nextjs-auth0/commit/98c36dc306970c2230ea1a32efef431d29b99978
github.com/auth0/nextjs-auth0/releases/tag/v4.18.0
github.com/auth0/nextjs-auth0/security/advisories/GHSA-xq8m-7c5p-c2r6
nvd.nist.gov/vuln/detail/CVE-2026-40155

Code Behaviors & Features

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