CVE-2026-40583: UltraDAG权限绕过导致状态篡改漏洞

// Conceptual Proof of Concept for CVE-2026-40583 // This demonstrates the vulnerable logic flow in UltraDAG v0.1 struct Transaction { sender: String, signature: Vec<u8>, nonce: u64, payload: Payload, } enum Payload { Vote { candidate: String }, } struct State { votes: HashMap<String, u64>, } // Simulating the vulnerable function fn process_transaction_vulnerable(tx: &Transaction, state: &mut State) -> Result<(), String> { // Step 1: Prechecks (Signature, Nonce, Balance) // Attacker passes these easily with a valid account if !verify_signature(&tx) { return Err("Invalid Signature".to_string()); } if !check_nonce(&tx) { return Err("Invalid Nonce".to_string()); } // VULNERABILITY: State mutation happens BEFORE authorization check // The system applies the vote to the state if let Payload::Vote { candidate } = &tx.payload { *state.votes.entry(candidate.clone()).or_insert(0) += 1; println!("State mutated: Vote recorded for {}", candidate); } // Step 2: Authorization Check // This check happens too late. Even if it fails, state is already changed. if !is_council_member(&tx.sender) { // In the vulnerable version, this error might be returned, // but the state mutation above is not rolled back effectively. return Err("Authorization Failed: Sender is not a council member".to_string()); } Ok(()) } // Helper stubs fn verify_signature(_tx: &Transaction) -> bool { true } fn check_nonce(_tx: &Transaction) -> bool { true } fn is_council_member(sender: &str) -> bool { // Attacker is not in the council sender != "attacker" }