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:
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:
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