Redhat & CentOS 6.x and CentOS 7.3 and lower have a new Linux Kernel security update for security vulnerability CVE-2017-1000253. OpenVZ VPS users don't use their own Linux Kernels like dedicated, KVM or Xen users so need to make sure their OpenVZ VPS provider's host node kernel is updated. Info https://www.qualys.com/2017/09/26/cve-2017-1000253/cve-2017-1000253.txt Updating Linux Kernel So need to do 2 steps for non-openvz systems. For openvz vps you use host node kernel and not your own so only your web host can update the host node kernel so contact them. Some openvz vps providers also use KernelCare so are auto patched up but some don't. Do a yum update Code (Text): yum -y update then check if updated kernel version is updated via Code (Text): yum list kernel output Then reboot your server for Kernel update to take effect. If you use KernelCare KernelCare rebootless kernel updates - CentminMod.com LEMP Nginx web stack for CentOS they auto patch your kernel every 4hrs and do not require server reboots. Then verify after reboot of kernel version via Code (Text): uname -r or if using KernelCare via Code (Text): kcare-uname -r Update SSH Commands Updating yum packages via yum update Code (Text): yum -y update After update and server reboot verify updated kernel with command Code (Text): uname -r or if using KernelCare via Code (Text): kcare-uname -r Summary Redhat/CentOS 6.x users need to update to Linux Kernel 2.6.32-696.10.3 as per https://access.redhat.com/errata/RHSA-2017:2795 and then reboot their servers. Redhat/CentOS 7.x users best to update to 7.4 OS which has fixed Linux Kernel 3.10.0-693 or higher.