Tag Archives: centos

openvas

Openvas installation in CentOS 7

How To, linux, networking, security, shell, , ,

What is Openvas?

OpenVAS (Open Vulnerability Assessment System, originally known as GNessUs) is a software framework of several services and tools offering vulnerability scanning and vulnerability management.

All OpenVAS products are free software, and most components are licensed under the GNU General Public License (GPL). Plugins for OpenVAS are written in the Nessus Attack Scripting Language, NASL.

The primary reason to use this scan type is to perform comprehensive security testing of an IP address. It will initially perform a port scan of an IP address to find open services. Once listening services are discovered they are then tested for known vulnerabilities and misconfiguration using a large database (more than 53000 NVT checks). The results are then compiled into a report with detailed information regarding each vulnerability and notable issues discovered.

Once you receive the results of the tests, you will need to check each finding for relevance and possibly false positives. Any confirmed vulnerabilities should be re-mediated to ensure your systems are not at risk.

Vulnerability scans performed from externally hosted servers give you the same perspective as an attacker. This has the advantage of understanding exactly what is exposed on external-facing services.

Step 1: Disable SELinux

“`

sed -i ‘s/=enforcing/=disabled/’ /etc/selinux/config

“`

and reboot the machine.

Step 2:  Install dependencies

“`

yum -y install wget rsync curl net-tools

“`

Step 3: Install OpenVAS repository

install the official repository so that OpenVAS works appropriately in the analysis of vulnerabilities.

“`

wget -q -O – http://www.atomicorp.com/installers/atomic |sh

“`

Step 4: Install OpenVAS

“`

yum -y install openvas

“`

Step 5: Run OpenVAS

Once OpenVAS is installed, we continue to start it by executing the following command:

“`

openvas-setup

“`

Once downloaded it will be necessary to configure the GSAD IP address, Greenbone Security Assistant, which is a web interface to manage system scans.

Step 6: Configure OpenVAS Connectivity

We go to our browser and enter the IP address of the CentOS 7 server where we have installed OpenVAS, and we will see that the following message is displayed:

Openvas dashboard

 

Automatic NVT Updates With Cron

“`

35 1 * * * /usr/sbin/greenbone-nvt-sync > /dev/null
5 0 * * * /usr/sbin/greenbone-scapdata-sync > /dev/null
5 1 * * * /usr/sbin/greenbone-certdata-sync > /dev/null

“`

 

How to install Asterisk on CentOS

How To, ,

In this installment of our How To, we are going to go over on the topic of how to install Asterisk on CentOS. For this we are going to use Asterisk 13 and CentOS 7 minimal version. But, instructions will mostly be similar to other versions of Asterisk and CentOS.

As a first step you need to download latest asterisk on to your machine. For this you need wget tool. As we are using minimal flavor of CentOS even wget tool is not available on fresh install. Run the following command to install wget.

yum install wget

Once, wget is installed successfully, run the following command to download asterisk.

wget http://downloads.asterisk.org/pub/telephony/asterisk/asterisk-13-current.tar.gz

Extract downloaded asterisk tar ball

tar -zxvf asterisk-13-current.tar.gz
cd asterisk-13.6.0

Install the following dependencies

yum install gcc
yum install gcc-c++
yum install ncurses-devel
yum install uuid-devel libuuid-devel
yum install jansson-devel
yum install libxml2-devel
yum install sqlite-devel

Once, all the above dependencies are installed. You can now run the following command to enable or disable modules of your choice.

make menuselect

After you are done with the menuselect screen, run the following command to compile and install asterisk

make
make install
make samples

That’s it now you have asterisk installed successfully on your you machine. Run, the following command to start asterisk

asterisk -vvvvgc

Now, you should see asterisk console saying “Asterisk Ready”. Instead, if you encounter the following error

/usr/bin/asterisk: error while loading shared libraries: libasteriskssl.so.1: cannot open shared object file: no such file or directory.

Don’t worry, just run the following command and start asterisk again after that.

ldconfig