The GHOST Vulnerability (and yes, this blog is still alive :))

After Heartbleed and Poodle in 2014, it's now time for the first major security vulnerability in Linux systems in 2015 : GHOST The GHOST vulnerability is a serious weakness in the Linux glibc library which allows attackers to remotely take complete control of the victim system without having any prior knowledge of system credentials. CVE-2015-0235 has been assigned to this issue. You can read more about this issue here : https://community.qualys.com/blogs/laws-of-vulnerabilities/2015/01/27/the-ghost-vulnerability You can list all packages/applications depends upon vulnerable Glibc, by running the following command on your server : lsof | grep libc | awk '{print $1}' | sort | uniq As you can see, a lot of packages are using Glibc library on Linux. If you want to check your glibc version, you can run : ldd --version Now, to patch your Ubuntu/Debian server, ...

How to stress-test a CPU on a Linux server

In some cases, you may want to voluntarily stress-test the CPU of a Linux server to see what happens (monitoring stuff for example). Method First, create a file on your hard drive with the following command: dd if=/dev/urandom of=testfile count=20 bs=1024k Next, create a shell script with a md5sum loop as below, and named it "stress_cpu": #!/bin/sh i=0 while [ 1 ] do md5sum testfile i=`expr $i + 1` echo "Iteration: $i" done Make the script executable : chmod +x stress_cpu Then, you just need to execute it and your CPU load will increase instantly. ./stress_cpu Ctrl-C will end it, as always. ...