CVE-2026-73683

Laravel Socialite's Facebook provider contains an authentication bypass vulnerability that allows unauthenticated attackers to replay captured OIDC id_tokens by exploiting the missing nonce claim validation in the getUserByOIDCToken() function within FacebookProvider.php. Attackers who obtain a valid, unexpired id_token issued for the same Facebook App ID can submit the captured token to the backend userFromToken() endpoint, bypassing authentication controls because signature, aud, and iss checks pass while no session-bound nonce comparison is performed, resulting in unauthorized access to victim accounts.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/laravel/socialite
https://github.com/laravel/socialite/commit/caf714f55d51ab0d914b40033d8b0f489d6219cc
https://github.com/laravel/socialite/pull/789
https://www.vulncheck.com/advisories/laravel-socialite-facebook-provider-authentication-bypass-via-nonce-replay

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-14 22:17

Updated : 2026-08-18 03:16

NVD link : CVE-2026-73683

Mitre link : CVE-2026-73683

CVE.ORG link : CVE-2026-73683

JSON object : View

Products Affected

No product.

CWE

CWE-294

Authentication Bypass by Capture-replay

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