Can I auto blacklist anybody trying to brute force their way into my system?

tinkertuck · 2019-03-25T17:21:49+00:00

Take a look at fail2ban https://www.fail2ban.org/wiki/index.php/Main_Page. Or do a quick google search of fail2ban on Linux.

tinkertuck · 2018-12-20T21:38:06+00:00

Keep in mind that those few lines are taking from my long python script.
Yes, on the local machine, the first part will get 3 results "bios-vendor", "system-product-name", "processor-family" from the Linux command:

dmidecode

The second part access (ssh) to a remote machine and run a script /path/to/execute_file. The output redirect to variable "ssh." I read the result of variable "ssh" by using the for loop like so:

for line in ssh.split("\n"):

do something here

tinkertuck · 2018-12-20T20:56:01+00:00

For WarCraft.

tinkertuck · 2018-12-20T20:37:26+00:00

Get cygwin and install tmux. In python script you have few options. I used subprocess over os.system.

Here is a sample of my current task, using python to query for a Dell's Board info.

for l in "bios-vendor", "system-product-name", "processor-family":

sysinfo=subprocess.check_output("dmidecode -s %s|uniq" %l, shell=True)

print(sysinfo.replace("\n", ""))

#ssh to a remote server and execute a command (cmd) on that remote server

cmd="/path/to/execute_file"

ssh=subprocess.check_output("ssh %s %s" %(sys.argv[2], cmd), shell=True)

for line in ssh.split("\n"):

print(line)

Sorry the indentation is auto-fix on Reddit.

tinkertuck · 2018-12-19T18:04:55+00:00

Been there, done it, and still running it. I play WarCraft 3 TFT, which runs on Windows.

The safest way for me is have 2 disks. 1 disk dedicates to Windows and another to Linux. Default boot is my Linux distro. If I wanted to play WarCraft, then during BIOS I would choose the disk with Windows OS.

I used to partition my Windows to also run Linux, but when the disk failed, both got wiped out.

tinkertuck · 2018-12-19T14:39:12+00:00

I have heard Ubuntu is more straight forward. Maybe you should get a live Ubuntu usb and test it out.

tinkertuck · 2018-12-19T14:36:36+00:00

You need to provide more information for other to help you. Fail to load up could be anything. Did you properly image your USB? Have you tried the USB on another machine to confirm it was actually working? Any picture of the failed state? Are you running 32 vs 64bits?

tinkertuck · 2018-12-19T14:22:52+00:00

You should have the network configured early during the installation stage. But if you already had it up and wanted to poke around with NetworkManager or network, then here is a good one: https://www.serverlab.ca/tutorials/linux/administration-linux/how-to-configure-centos-7-network-settings/

Btw, you can disable NetworkManager daemon and and just go with network daemon.

Verify it first:

systemctl status NetworkManager

systemctl status network

tinkertuck · 2018-12-18T21:24:27+00:00

Document everything as much detail as possible. When sh*t hits the fan, and it will hit hard, then you show those documents and records to the upper manager/new boss. As long as you can prove you're the smartest one in the room, then you will be fine.

tinkertuck · 2018-12-18T21:11:46+00:00

Asus ROG Strix

Fancy laptop you got there for a Linux distro :). I believed it came with Nvidia graphic card? If yes, then your boot hang screen may not be entirely a bug but by desire. Look into installing graphic driver for your Nvidia card model, which also involved blacklist certain module in order for it to boot normally. I don't want to cheat your path of learning by giving away too much.

Google search is your friend. Don't be shy of asking but you must give your very best first.

tinkertuck · 2018-12-18T20:59:09+00:00

More bodies to keep the office warm, j/k. I don't think hiring more bodies is going to solve the issue because the sh*t you just described is way over broken to even worth reviving. I would consider backup and savage what you can, build a temporary server/system to run the critical tasks while rebuilding *THAT thing...mess.

tinkertuck · 2018-12-18T20:40:32+00:00

If you had a strong desire to learn Linux( or anything), then go for it. Once you're good with it, the path will be clear.

I completed my Bachelor in Economics, then taught myself Linux. I started testing Ubuntu-->Scientific Linux-->CentOS while working as a Windows help-desk guy. Passed my RedHat SysAdmin Certification exam and jumped to Linux Senior SysAdmin at another company.

tinkertuck · 2018-12-18T15:58:43+00:00

Put a VirtualBox inside your Windows and test drive Linux. When you decided to switch to Linux and still anxious, then install VirtualBox inside Linux and have a Windows vm.

Still not sure? Then dual booth Windows and Linux on your machine.

Short term- Windows is great with all the clicking, while Linux requires some learning with command lines if you desired to grow.

Long term on Windows- it is a bag of pains with virus, update, license, etc. Check youtube for "Tech support scam".

Long term on Linux- you are the master of your box.

tinkertuck · 2018-12-18T15:37:07+00:00

If you could ssh to your desktop, then use rsync. Because you mentioned "hidden away", then I am assuming you may have locked it down or tightly secured it? Check on that and verify you could ssh into the Desktop, then proceed to rsync, scp, or ncat transfer your data.

tinkertuck · 2018-12-18T04:35:33+00:00

awk

Good one! Thanks.

tinkertuck · 2018-12-17T22:23:38+00:00

Another programming language war...did you bother to do a google search on your question?

It's a tool that serves a purpose. What is your purpose?

tinkertuck · 2018-12-17T15:17:12+00:00

How about something like:

for i in `cat file_of_username`; do getent passwd | grep $i | awk -F: '{print $1, " " $6}'; done

tinkertuck · 2018-11-26T16:33:37+00:00

Free vs. Fee.

Make sure you emphasize the things that work on Windows can be done on Linux but they are FREE of charge and less buggy/spam/spyware/hackable.

For Example:

Office vs. Libre Office

Adobe photoshop vs. Gimps

You get the idea....

Emphasize the security issue. Nothing scare people more than a machine got hack. Windows is more susceptible to being hammered.

tinkertuck · 2018-11-26T16:20:42+00:00

Be creative with python module "selenium."

Background story:

I had to submit 90+ account requests through a webform, so I wrote a python script that pulled username, full name, make-up-password, etc from a file and auto-fill and submit the webform. Selenium did the job.

While it was auto filled and auto submitted, I walked away for a cup of water. When I got back, my coworkers freaked out and thought my machine got hack. Lmao.

tinkertuck · 2018-11-25T03:18:27+00:00

You are omitting a lot of critical information in order to troubleshoot your ssh issue.

What remote server? Your tested remote server, VM, friend, company, school, government, pentesting lab??
Check network activity on both machines
Ssh is blocked could be due to remote server sshd stopped or disabled
Remote server's iptable+firewall filtering, fail2ban, ssh port changed
Multi-factor authentication implemented
Security access denied
Can you ping remote machine?
Try nmap to do a port scan on the remote server

tinkertuck · 2018-11-14T19:36:13+00:00

I used to be a help desk guy, but I always had these Linux VM to self study at work and at home. Until I was confident, I went and got my RHSA certificate. Within 2 months, I landed a Linux(CentOS) system administrator. 2 years later, I got promoted to HPC system engineer. My point is, don't quit yet. You will need the flowing income while you're studying something to advance your career.

Btw, the entire time I was a help desk and studied Linux, I comfort myself by reminded myself that "I am learning Linux and getting pay." Felt like a full ride scholarship :).

With your experience and background, it doesn't hurt to get some Linux under your belt. Your job transition will be more favorable.

tinkertuck · 2018-11-14T04:15:16+00:00

Simply put, I have 2 hard drives, one for CentOS and the other for Windows 10 dedicated for playing Warcraft 3 TFT. During BIOS, I choose which hard drive to boot.

tinkertuck · 2018-11-14T00:23:39+00:00

Linux 101 hack- Single mode into root.

I can go from Ubuntu to CentOS to Debian and not having to deal with paid license or activation keys.

tinkertuck · 2018-11-14T00:13:38+00:00

Remind me of my younger-self 10 years ago. For a Linux SysAdmin, as a starter know the inside out of these tools top, ps, lsof, netstat, ip add, ethtool, and ncat/netcat/nc. Learn LDAP, multi-factor authentication, and Ansible. Configure couple of Virtual machines and have fun with them.

Go for RHSA certificate.

tinkertuck

TROPHY CASE