CVE-2026-40155
5.4 · MEDIUMOverview
CVE-2026-40155 is a medium-severity vulnerability affecting auth0 nextjs-auth0. It was published on April 17, 2026 and has a CVSS 3.1 base score of 5.4 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.4, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
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.
Remediation
Check the references section for vendor advisories and patches from auth0. Update nextjs-auth0 to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| auth0 | nextjs-auth0 | >= 4.12.0, < 4.18.0 | Affected |
Frequently Asked Questions
What is CVE-2026-40155?
CVE-2026-40155 is a medium-severity vulnerability affecting auth0 nextjs-auth0. It was published on April 17, 2026 and has a CVSS 3.1 base score of 5.4 (MEDIUM).
How severe is CVE-2026-40155?
This vulnerability has a CVSS 3.1 base score of 5.4, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-40155?
Check the references section for vendor advisories and patches from auth0. Update nextjs-auth0 to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-40155?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-40155 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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