CVE-2026-39976

Name: CVE-2026-39976
Creator: NVD / NIST
Published: 2026-04-09T17:16:31.267+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.1/10EPSS 0.29%

Last modified Jun 17, 2026

CVE-2026-39976 is a high-severity vulnerability rated 7.1/10 on the CVSS scale. Laravel Passport provides OAuth2 server support to Laravel. From 13.0.0 to before 13.7.1, there is an Authentication Bypass for client_credentials tokens. EPSS estimates a 0.29% chance of exploitation in the next 30 days.

Description

Laravel Passport provides OAuth2 server support to Laravel. From 13.0.0 to before 13.7.1, there is an Authentication Bypass for client_credentials tokens. the league/oauth2-server library sets the JWT sub claim to the client identifier (since there's no user). The token guard then passes this value to retrieveById() without validating it's actually a user identifier, potentially resolving an unrelated real user. Any machine-to-machine token can inadvertently authenticate as an actual user. This vulnerability is fixed in 13.7.1.

Metrics

CVSS 3.1

7.1/10

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N

EPSS Probability

0.29%

20.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-287

Affected Software

Vendor	Product	Versions
Laravel	Passport	>= 13.0.0, < 13.7.1

References

https://github.com/laravel/passport/issues/1900Exploit, Issue Tracking
https://github.com/laravel/passport/pull/1901Issue Tracking, Patch
https://github.com/laravel/passport/pull/1902Issue Tracking, Patch
https://github.com/laravel/passport/security/advisories/GHSA-349c-2h2f-mxf6Mitigation, Vendor Advisory
https://github.com/thephpleague/oauth2-server/issues/1456#issuecomment-2734989996Issue Tracking, Patch

Timeline

Published: Apr 9, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-39976?

How severe is CVE-2026-39976?

CVE-2026-39976 has a CVSS score of 7.1/10 (HIGH severity). The EPSS model estimates a 0.29% probability of exploitation in the next 30 days.

How do I fix CVE-2026-39976?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-39976?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST