Category Archives: Security

What is GRSecurity

Grsecurity® is an extensive security enhancement to the Linux kernel that defends against a wide range of security threats through intelligent access control, memory corruption-based exploit prevention, and a host of other system hardening that generally require no configuration. It has been actively developed and maintained for the past 15 years. Commercial support for grsecurity is available through Open Source Security, Inc.

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Thousands Linux and FreeBSD Servers Infected with Mumblehard Spamming Malware

The sophisticated Mumblehard spamming malware infects thousands of Linux and FreeBSD servers going under the radar for at least five years. In the last seven months, several thousand Linux and FreeBSD machines have been infected with a sophisticated malware dubbed Mumblehard. The infected machines were part of a botnet used, in the last five years, to run spam campaign, a version of the Mumblehard malware was uploaded to the VirusTotal online malware checking service in 2009.

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How to Test WordPress Security using Open Source Security tool WP-SCAN

Before I dive in this post, I would like to say that everything here for educational purposes only! Now we can move on. WordPress is exceptionally prevalent, on the grounds that is the most easy to use CMS (Content Management System) in the World. Numerous essential organizations or superstars are utilizing WordPress for their sites, for example, Ford, Sony PlayStation, CNN, The Rolling Stones, and UPS etc.

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Installation & configuration of ModSecurity on APACHE

Mod Security is a web based firewall (WAF) designed for apache (though there is a version available for IIS too). It is widely used and highly effective. But there is a learning curve in using modsec. You can start exploring by installing ModSec on your system. INSTALLATION USING YUM To install modsec from YUM you will need to install EPEL ( Extra Packages for Enterprise Linux ) Depending upon your Linux installation run the following command [yOMan@ x-machine ~]# uname -a      Linux 2.6.18-308.1.1.el5…

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Setting up 802.1q VLAN tagging by loading 8021q Linux kernel driver Check that Linux kernel driver module called 8021q is loaded: # lsmod | grep 8021q If it is not loaded, load it with the following modprobe command: # modprobe 8021q How to VLAN Linux usingCentOS/RHLE/Fedora Linux I am using RHEL/CentOS Linux with VLAN ID # 5. So I need to copy file /etc/sysconfig/network-scripts/ifcfg-eth0 to /etc/sysconfig/network-scripts/ifcfg-eth0.5 # cp /etc/sysconfig/network-scripts/ifcfg-eth0 /etc/sysconfig/network-scripts/ifcfg-eth0.5 Now, I’ve one network card (eth0) and it needs to tagged network traffic for VLAN…

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Installing Nagios core on RHEL / CENTOS 5.x – RHEL / CentOS 6.x Fedora 15/16/17/18/19/20

What is Nagios An enterprise-class monitoring and alerting solution that provides organizations with extended insight of their IT infrastructure before problems affect critical business processes. Requirements We require following things for Installing Nagios: These are Just Pre-requisites. We need them to other things work … 1. Apache and PhP (php is optional) 2. gcc, glib, glibc-common, gd and gd-devel

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Snort RPM Based Installation with SnortSnarf and Snort Rule Creation Methods on Linux RHEL /CentOS / Fedora

RPM Based Installation of Snort with SnortSnarf and Snort Rule Creation Methods: written by: Muhammad Farrukh Siddique Snort is an open source Network Intrusion Detection System Snort can also act as Sniffer and Logger In this section we will discuss the more beneficial part of Snort that is Intrusion Detection System (IDS) Snort can also be installed on Windows Platform which will be covered later. Currently the Operating System is CentOS-5.3 Snort Installation and Configuration: First of all download and install the following required packages…

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HTop – CPU, Memory & Process Monitoring Utility in Linux by Qasim Mehmood


Htop is a text-mode, interactive process viewer for Linux run via console/ssh, and to install htop on Linux is a pretty simple task. Among other things, htop allows you the following:

  • Quickly view key performance statistics such as CPU(multi-core layout), Memory and Swap usage Details.
  • Scroll the process list vertically and horizontally to see all processes and complete command lines.
  • Kill processes by selection rather than entering process number, use mouse to select list items.
  • PuTTY (the Telnet and SSH client) can be used for the interface at client.

How to install Htop

You can easily install htop on CentOS 6.x using yum, but first you need to install the rpmforge package repository applicable to your architecture 32bit or 64bit (if already not installed) by using the following commands:

Install RPM for CentOS 6.x


rpm -Uhv rpmforge-release*.rf.i386.rpm



rpm -Uhv rpmforge-release*.rf.x86_64.rpm

Once the repository is installed, all you need to do to install htop in CentOS is run the following:

yum install htop

Now run the following command at command prompt or in PuTTy to start htop processes viewer.


After the installation of Htop, you can view the manual and other utilities of Htop, with the following commands.

[qasim@server ]# man htop                                           To view manual of htop, having complete details.

[qasim@server ]#htop -h                                                 To view different options/plug-ins.

[qasim@server ]#htop -u username                            To view the active user’s currently running processes information.

[qasim@server ]#htop -u qasim                                    To view the qasim’s currently running processes information.

[qasim@server ]#htop -u root                                       To view the root’s currently running processes information