# CVE-2026-42280: Auth0 Auth0.js incorrect authorization in user profile retrieval

Source: https://junglewise.ai/threats/cve-2026-42280-auth0-auth0-js-incorrect-authorization-in-user-profile-retrieval  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-27. Updated: 2026-06-09  
License: CC BY 4.0 with a link back

CVE-2026-42280 · Severity: high · CVSS 7.1 · Published 2026-05-27

The Auth0.js SDK, a library used to integrate authentication into web applications, contains a flaw in how it validates user identity. Under specific conditions, an attacker could provide a specially crafted token to bypass certain security checks and access sensitive user profile information. This could lead to unauthorized data exposure for applications that rely on Auth0 Actions for access control.

Technologies: [auth0-js (npm)](https://junglewise.ai/threats/technologies/auth0-js). Vendors: [npm](https://junglewise.ai/threats/vendors/npm).

## Quick answers

**Is CVE-2026-42280 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-42280 being exploited in the wild.

**How severe is CVE-2026-42280?** High severity, with a CVSS score of 7.1, published 27 May 2026.

**Which products and versions are affected?** auth0-js (npm) >= 8.11.0, <= 9.32.0, SEMVER:introduced=8.11.0,fixed=10.0.0.

**Is there a fix for CVE-2026-42280?** Yes. auth0-js (npm): upgrade to 10.0.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-42280 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-42280?** Check whether you run auth0-js (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- auth0-js (npm): upgrade to 10.0.0 or later

  ```sh
  npm install auth0-js@10.0.0
  ```


## Technical details

An incorrect authorization vulnerability (CWE-863) exists in the Auth0.js SDK versions 8.11.0 through 9.32.0. The root cause is improper permission checking when processing a valid access token in conjunction with a specifically crafted, invalid ID token. This vulnerability is exploitable if the application's access control logic relies on rules defined in Auth0 Actions. A remote attacker with low privileges can exploit this over the network without user interaction to retrieve user profile data that should otherwise be protected. The issue is resolved in version 10.0.0.

## Affected products

- Auth0 auth0-js 8.11.0 to 9.32.0

## Identifiers

- CVE-2026-42280
- GHSA-8qjv-jj2q-x832

## Timeline

- 2026-05-06: disclosed
- 2026-05-06: advisory
- 2026-05-06: patched: Fixed in version 10.0.0

## References

- [https://github.com/auth0/auth0.js/security/advisories/GHSA-8qjv-jj2q-x832](https://github.com/auth0/auth0.js/security/advisories/GHSA-8qjv-jj2q-x832)
- [https://api.github.com/repos/auth0/auth0.js/security-advisories/GHSA-8qjv-jj2q-x832](https://api.github.com/repos/auth0/auth0.js/security-advisories/GHSA-8qjv-jj2q-x832)

## Related threats

- [Auth0 auth0.js information disclosure in error object](https://junglewise.ai/threats/cve-2020-5263-auth0-auth0-js-information-disclosure-in-error-object)
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- [Auth0 auth0-js CSRF bypass in state parameter validation](https://junglewise.ai/threats/cve-2018-7307-auth0-auth0-js-csrf-bypass-in-state-parameter-validation)
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