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CVE-2026-39976

Laravel Passport's TokenGuard Authenticates Unrelated User for Client Credentials Tokens

Published: Apr 9, 2026Updated: Jun 2, 2026 Sources: CVE List NVD BDUCWE-287
NVD MITRE
7.1CVSSHIGH
EPSS Score
0.3%
Top 79.6%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

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.

CVSS Vector Breakdown

AV:NAC:HPR:LUI:NS:CC:HI:LA:N
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:CScope
Changed
Impact
C:HConfidentiality
High
I:LIntegrity
Low
A:NAvailability
None
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Weaknesses

CWE-287

Affected Products

passportlaravel
On-prem
OSS Libraries / web-framework
Laravel PassportTaylor Otwell
Library
OSS Libraries / web-framework
laraveloss-projectUSOSS Librariesaka laravel framework, livewire
taylor otwellindividual-devAUOSS Librariesaka laravel, laravel octane, laravel passport

Attack Graph

Products CVE Techniques Tactics

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Exploitability

Official Patch Available
Workaround Available

MITRE ATT&CK

2 techniques
Initial Access
View detailed technique mapping

References

https://github.com/laravel/passport/security/advisories/GHSA-349c-2h2f-mxf6
github.com
https://github.com/laravel/passport/issues/1900
github.com
https://github.com/thephpleague/oauth2-server/issues/1456#issuecomment-2734989996
github.com
and 4 more references View all →

Timeline

Published
Apr 9, 2026
Last Updated
Jun 2, 2026

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