≡ Menu

Security

How To Patch and Protect Linux Kernel Zero Day Vulnerability CVE-2016-0728 [ 19/Jan/2016 ]

A very serious security problem has been found in the Linux kernel. A 0-day local privilege escalation vulnerability has existed since 2012. This bug affects millions of Android or Linux applications to escalate privileges. Any server or desktop (32 or 64 bit) with Linux Kernel version 3.8+ is vulnerable. How do I fix this problem?
[click to continue…]

How to block an IP address with ufw on Ubuntu Linux server

I am using UFW to manage firewall on my Ubuntu Linux 12.04/14.04 LTS server. I need to block a specific IP address from accessing my server. How do I block an IP address using ufw?
[click to continue…]

How to secure and lock down Apple OS X 10.11 (El Capitan) with osxlockdown

Is there is an easy way to audit and lock down (secure) Apple OS X 10.11 (El Capitan) unix operating system?
[click to continue…]

I setup a web-server. I need to grant a user ssh access but I do not trust users. How can I limit user session to a specific directory such as /home/httpd/$USERNAME? How do I set up a ssh chroort jail on a Linux operating systems?
[click to continue…]

A very serious security problem has been found in the virtual floppy drive QEMU's code used by many computer virtualization platforms including Xen, KVM, VirtualBox, and the native QEMU client. It is called VENOM vulnerability. How can I fix VENOM vulnerability and protect my Linux server against the attack? How do I verify that my server has been fixed against the VENOM vulnerability?
[click to continue…]

RHEL / CentOS Linux 7 Enable Ping Access In Docker Container

I'm using RHEL 7.1-4 container on a RHEL /CentOS Linux 7.x server. However, I'm unable to ping external site/IP address using the ping command. I'm getting the following error on screen:

ping: Operation not permitted

How do I fix this problem?
[click to continue…]

I am a Debian Linux serer user. How do I view the changelog of an installed package and find out if given CVE includes a fix or patch? How do I see a fix or patch already applied to installed package on a Ubuntu or Debian LTS server?
[click to continue…]

On 19th March 2015, multiple high and moderate severity level vulnerabilities released in OpenSSL, a Secure Sockets Layer toolkit used in a Linux and Unix-like systems. How can I fix these vulnerabilities on a CentOS/RHEL/Ubuntu and Debian Linux based server for OpenSSL versions 1.0.2a, 1.0.1m, 1.0.0r, and 0.9.8zf.? How do I verify that my Linux server has been fixed against the OpenSSL vulnerability?
[click to continue…]

FreeBSD Unix Find Out Which Programs Are Listing On a Given Port Number

I'm a new FreeBSD Unix system user. How can I find out the process/programs names listing on a certain port on a FreeBSD Unix systems using command line? How do I lookup the process which is currently bound to the given network port on a FreeBSD server?
[click to continue…]

Ubuntu Linux: Edit and Open Files That Require Administrator Privileges

There are certain files in Ubuntu Linux (or Unix-like systems) that only root user access or edit. How can I edit and/or open files that requires admin (root) access on a Ubuntu Linux?
[click to continue…]