CVE-2026-107371 Auth0 CVE debrief

Who should care

Defenders responsible for authentication and authorization in applications using the auth0.js library should assess the vulnerability and prioritize verification of the library version and authentication event age validation.

Why it matters

The CVE-2026-107371 vulnerability in the auth0.js library may allow applications to process ID tokens representing older authentication events, potentially bypassing authentication event age verification.

• Verification of authentication event age may be bypassed.
• Applications may process ID tokens representing older authentication events.

Technical summary

The auth0.js library does not validate the auth_time claim in the ID token when the authorize() method is called with a maxAge parameter. This oversight may allow an application to process an ID token representing an authentication event older than the requested maximum age, potentially bypassing authentication event age verification. Defenders should prioritize verifying the auth0.js library version and assessing the authentication event age validation in their applications. The CVE Program record and NVD vulnerability detail provide official information about the vulnerability.

Defensive priority

Defenders should prioritize verifying the auth0.js library version and assessing the authentication event age validation in their applications.

Recommended defensive actions

• Verify the auth0.js library version used in your application.
• Assess the authentication event age validation in your application.
• Consider updating the auth0.js library to version 10.3.0 or later.
• Review compensating controls for exposed systems while remediation is scheduled and verified.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The CVE Program record and NVD vulnerability detail provide official information about the vulnerability. The auth0.js library's missing verification of the auth_time claim may impact authentication event age validation.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.