CVE-2026-73683

What it is

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.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.

Exploit odds

0.8% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-08-14 22:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-09-24 20:06 UTC Last updatedMost recent change to the record

Details

Published

2026-08-14 22:17 UTC

Last modified

2026-09-24 20:06 UTC

Exploit probability

0.8% · EPSS, next 30 days

Weakness

CWE-294

Record status

Deferred

Attack profile CVSS 4.0 · 9.2

Attack vector

Network

Complexity

High

Attack requirements

None

Privileges needed

None

User interaction

None

Confidentiality

High

Integrity

High

Availability

High