How severe is CVE-2026-39976?

CVE-2026-39976 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.

Is CVE-2026-39976 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-39976?

CVE-2026-39976 affects Laravel Passport. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-39976?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-39976 have an EU (EUVD) identifier?

Yes. CVE-2026-39976 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20970.

When was CVE-2026-39976 published?

CVE-2026-39976 was published on 2026-04-09 and last updated on 2026-06-17.

CVE-2026-39976

CVE-2026-39976 is a high-severity vulnerability in Laravel Passport with a CVSS 3.x base score of 7.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: High (CVSS 3.x base score 7.1)
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-20970
Weakness: CWE-287
Affected product: Laravel Passport
Published: 2026-04-09
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2026-39976?: 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.
How severe is CVE-2026-39976?: CVE-2026-39976 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.
Is CVE-2026-39976 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-39976?: CVE-2026-39976 affects Laravel Passport. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-39976?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-39976 have an EU (EUVD) identifier?: Yes. CVE-2026-39976 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20970.
When was CVE-2026-39976 published?: CVE-2026-39976 was published on 2026-04-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:laravel:passport:*:*:*:*:*:laravel:*:*

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