How to Use the Screen Command in Linux

Reading Time: 6 minutes

What is Screen?

Screen is a terminal program in Linux which allows us to use a virtual (VT100 terminal) as full-screen window manager which multiplexes an open physical terminal between multiple processes, which are typically, interactive shells. It allows us to access multiple terminal sessions within a single terminal or a remote terminal session. It is most useful when addressing multiple Linux shell commands on the command line, as well as separating commands from the shell that started the commands.

Continue reading “How to Use the Screen Command in Linux”

How to Update Bash on Fedora 20 and Fedora 21

Reading Time: < 1 minute

Please note that this article is considered legacy documentation because Fedora 20 and 21 has reached its end-of-life support.
Pre-Flight Check
  • These instructions are intended specifically for updating Bash on Fedora 20 and Fedora 21.
  • I’ll be working from both a Liquid Web Self Managed Fedora 20 server and a Liquid Web Self Managed Fedora 21 server, and I’ll be logged in as root.

Continue reading “How to Update Bash on Fedora 20 and Fedora 21”

CVE-2014-6271 and CVE-2014-7169 Info – Bash Vulnerabilities

Reading Time: 2 minutesOn September 24th, a vulnerability was reported in the GNU Bourne-Again-Shell (BASh, or Bash), specifically a flaw with how Bash processes values of environment variables, that allows remote code execution of varying types in many common configurations. The overall risk is severe due to bash being configured for use, by default, on most Linux servers.

While Liquid Web immediately began working to proactively patch this vulnerability, some servers may remain vulnerable depending on their update settings or other unforeseen intervening factors. Thus, we’ve provided the instruction below.

To Summarize:

  • This flaw exploits Bash, a Unix command-line shell run by default on most Linux servers.
  • Allows for remote code execution, and many types of command-line based attacks.
  • A patch is available, and your server can be easily updated.
  • We have tutorials on How to Update Bash on Red Hat and CentOS and How to Update Bash on Debian and Ubuntu.
  • Test the vulnerability of your server with the information below.

Continue reading “CVE-2014-6271 and CVE-2014-7169 Info – Bash Vulnerabilities”