mirror of
https://github.com/AbdullahRizwan101/CTF-Writeups
synced 2024-11-22 03:53:03 +00:00
Create Lock.md
This commit is contained in:
parent
6336794e6a
commit
2dd5178231
1 changed files with 144 additions and 0 deletions
144
Vulnlab/Lock.md
Normal file
144
Vulnlab/Lock.md
Normal file
|
@ -0,0 +1,144 @@
|
||||||
|
# Vulnlab - Lock
|
||||||
|
|
||||||
|
```
|
||||||
|
PORT STATE SERVICE VERSION
|
||||||
|
80/tcp open http Microsoft IIS httpd 10.0
|
||||||
|
445/tcp open microsoft-ds?
|
||||||
|
3000/tcp open ppp?
|
||||||
|
3389/tcp open ms-wbt-server Microsoft Terminal Services
|
||||||
|
5357/tcp open http Microsoft HTTPAPI httpd 2.0 (SSDP/UPnP)
|
||||||
|
```
|
||||||
|
|
||||||
|
## PORT 80
|
||||||
|
|
||||||
|
The webserver has template page hosted with just about section and nothing else
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/4lnStxV.jpeg"/>
|
||||||
|
|
||||||
|
## PORT 3000
|
||||||
|
|
||||||
|
On this port there's an instance of gitea being hosted, having a repository `dev-scripts`
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/lBiVOm4.png"/>
|
||||||
|
|
||||||
|
This repo has python script which is going to list down all the repository of the user with his `PAT` (Presonal Access Token).
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/D6w1iHX.png"/>
|
||||||
|
|
||||||
|
## Enumerating repoistories
|
||||||
|
|
||||||
|
Checking the commit history, we'll find gitea token
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/GCOhyqf.png"/>
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/8f7h3ph.png"/>
|
||||||
|
|
||||||
|
Copying the script on your local machine and using the token from commit history, the script will show another repo named `website`
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/Sh2aeEa.png"/>
|
||||||
|
Using the PAT we can clone this repo
|
||||||
|
|
||||||
|
```bash
|
||||||
|
git clone http://43ce39bb0bd6bc489284f2905f033ca467a6362f@10.10.109.226:3000/ellen.freeman/website.git
|
||||||
|
```
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/VKQ93pt.png"/>
|
||||||
|
|
||||||
|
## Uploading webshell
|
||||||
|
|
||||||
|
The `readme.md` from the repo, says that any changes made into this repo will be deployed on the webserver, so let's verify by creating a simple html file
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/0UsKUIX.png"/>
|
||||||
|
|
||||||
|
Adding the created html file with `git add file.html` also setting the username and email with `git config --global`
|
||||||
|
|
||||||
|
```
|
||||||
|
git add uwu.html
|
||||||
|
git config --global user.name "ellen.freeman"
|
||||||
|
git config --global user.email "ellen.freeman"
|
||||||
|
git commit -m "uwu"
|
||||||
|
git push
|
||||||
|
```
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/hzHzb9j.png"/>
|
||||||
|
|
||||||
|
Now this file will be deployed on the webserver
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/bRIzMFV.png"/>
|
||||||
|
|
||||||
|
Since IIS server is being used as a webserver (from the nmap scan), we can upload an aspx web shell https://github.com/tennc/webshell/blob/master/fuzzdb-webshell/asp/cmd.aspx
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/vmTcTOm.png"/>
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/xyiPJyv.png"/>
|
||||||
|
|
||||||
|
Transferring nc and getting a shell
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/oJHkf6S.png"/>
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/tYNorxp.png"/>
|
||||||
|
|
||||||
|
Under documents directory, we'll find `config.xml` which has an encrypted password for mRemoteNG
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/ypRB2Ir.png"/>
|
||||||
|
|
||||||
|
Using the script to decrypt the password https://github.com/gquere/mRemoteNG_password_decrypt/blob/master/mremoteng_decrypt.py
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/TVoNRvF.png"/>
|
||||||
|
Having the credentials, we can login as `gale.dakarios` through RDP, after logging we can see `PDF24` launcher on desktop
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/nTYVyMk.png"/>
|
||||||
|
|
||||||
|
## Escalating privileges through PDF24
|
||||||
|
|
||||||
|
Checking the version, it appears to be 11.15.1, which is vulnerable to local privilege escalation
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/iN8Xh1m.png"/>
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/c00KqTT.png"/>
|
||||||
|
|
||||||
|
The vulnerabilities lies with in the repair process of PDF24, the process calls `pdf24-PrinterInstall.exe` which gets executed with SYSTEM privileges with write access on faxPrnInst.log, with `SetOpLock` this file can then be blocked or to hold that file so the pdf24-PrinterInstall.exe will still remain open and we can then the perform the actions listed in the article
|
||||||
|
|
||||||
|
- right click on the top bar of the cmd window
|
||||||
|
- click on properties
|
||||||
|
- under options click on the "Legacyconsolemode" link
|
||||||
|
- open the link with a browser other than internet explorer or edge (both don't open as SYSTEM when on Win11)
|
||||||
|
- in the opened browser window press the key combination CTRL+o
|
||||||
|
- type cmd.exe in the top bar and press Enter
|
||||||
|
|
||||||
|
|
||||||
|
In C drive there's a hidden directory `_install` having pdf24 msi file
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/PJUC0tW.png"/>
|
||||||
|
|
||||||
|
Before running it make sure to have SetOpLock from here
|
||||||
|
https://github.com/googleprojectzero/symboliclink-testing-tools
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/Tc7wtFX.png"/>
|
||||||
|
|
||||||
|
Now executing the installer file with msiexec
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/o2cMxxh.png"/>
|
||||||
|
|
||||||
|
After sometime, we'll get a cmd window for pdf24-PrinterInstall.exe
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/NeryrDx.png"/>
|
||||||
|
|
||||||
|
Opening the properties of this window and clicking on legacy consolemodel link to open with firefox
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/s0qcpFW.png"/>
|
||||||
|
|
||||||
|
Use `ctrl+o` to open up a file and at the address bar type cmd.exe to spawn a shell as SYSTEM user because this whole process is being executed in the context on that user
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/BkSCkpD.png"/>
|
||||||
|
|
||||||
|
<img src="https://i.imgur.com/haaOHv1.png"/>
|
||||||
|
|
||||||
|
# References
|
||||||
|
|
||||||
|
- https://kettan007.medium.com/how-to-clone-a-git-repository-using-personal-access-token-a-step-by-step-guide-ab7b54d4ef83
|
||||||
|
- https://github.com/tennc/webshell/blob/master/fuzzdb-webshell/asp/cmd.aspx
|
||||||
|
- https://github.com/gquere/mRemoteNG_password_decrypt/blob/master/mremoteng_decrypt.py
|
||||||
|
- https://sec-consult.com/vulnerability-lab/advisory/local-privilege-escalation-via-msi-installer-in-pdf24-creator-geek-software-gmbh/
|
||||||
|
- https://github.com/googleprojectzero/symboliclink-testing-tools
|
||||||
|
|
Loading…
Reference in a new issue