I enjoy doing capture the flag boxes on sites like HackTheBox.eu, however I do come across the need for cracking passwords from time to time. My own graphics card is about ten years old and isn’t suited at all for password cracking.
I decided to check out the Azure N Series VMs as they have GPUs allocated and had success. I managed to take my time to crack SHA512 hashes with rockyou.txt from approx 8 hours down to 16 minutes. :)
I had some issues installing the NVidia drivers, but managed to sort it out in Step 11.
Step 1. Create a Resource Group.
Step 2. Add a VM in the Resource Group
Choose Ubuntu 18 LTS, and the Size “Standard NC6_Promo”.
Step 3. Choose the password options and set up your details.
Step 4. Disks – Choose Standard SSD.
Step 5. Networking – Leave the defaults, but enure “Public Inbound Ports” is set to SSH (22).
Step 6. Management – Unset the Boot Diagnostics.
Step 7. Review and Create – Select Create to create your VM.
Step 8. When your VM has been created, open the VM from the Azure Portal and take note of the “Public IP Address”.
Step 9. SSH to your VM
lspci to confirm the Tesla K80 card is installed
Step 11. Install the Nvidia Drivers following this guide: N Series Driver Setup
If you get the below problem, you can fix it using the following commands:
sudo dpkg -i --force-overwrite /var/cache/apt/archives/nvidia-440_440.64.00-0ubuntu1_amd64.deb
sudo apt-get --fix-broken install
sudo apt-get upgrade
Step 12. Reboot the VM.
Step 13. Verify driver install with
sudo apt install hashcat
hashcat -m 1800 <your hashfile> -o cracked.txt wordlists/rockyou.txt -w 3 -O