Vulnerability Assessment. A. Open Vulnerability Assessment (OpenVAS)

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1 Vulnerability Assessment After target discovery and enumeration, the next step is identifying critical security vulnerabilities in the target systems. Vulnerability assessment depends on the type and OS of the target. Vulnerability assessment can performed at the network, host, or application levels. At the end of this document, you will be asked to complete the third part of the project. Therefore, even though not required, it is highly recommended to test the steps as you read the document. A. Open Vulnerability Assessment (OpenVAS) The Open Vulnerability Assessment System (OpenVAS) is a collection of several services and tools offering a comprehensive vulnerability scanning and vulnerability management platform. OpenVAS is a client-server based application. In a network, a server will be typically dedicated to host OpenVAS. The users will connect to the OpenVAS server to perform vulnerability assessment of target. Configuration of OpenVAS is a lengthy process (see the instructions at The CVCLAB includes a preconfigured OpenVAS server. This document demonstrates how to perform vulnerability assessment using this OpenVAS server. This activity will be performed in your Windows 7 virtual machine. During the activity, you will be connecting an OpenVAS server using a client called Greenbone Security Desktop. Connecting to the OpenVAS server Start Greenbone Security Desktop (a link is available on the Desktop). Use the following information: Server: Port: 9390 Username: ptest Password: toor 1 of 9

2 After connecting to the OpenVAS center, the following window will appear. First, we will add a target and then add a scanning task, and finally we will execute the task and analyze the results. Running a task can taketoosome time so please be patient. 2 of 9

3 Adding a Target Let us now add a target to scan. Click the Targets tab (in the bottom windows) and then click the create button ( ) to add the host as shown below. Use your first name initial and last name in parentheses so that your scan will not interfere with others. In addition, your instructor will check the OpenVAS tasks and history to determine whether you have completed this step or not. 3 of 9

4 After adding the target host, it should appear in the Targets window as shown below. Adding Tasks In OpenVAS, a task means a Click the Tasks tab (in the bottom windows) and then click the create button ( ) to add a task as shown in the figure below. Name your task as your first name initial and last name. Select the target that you have created in the previous step. In this particular case, we will perform a Full and fast scan. 4 of 9

5 Click Create to add the task. If the task does not appear in the Tasks tab, click the refresh button ( ). Your task should appear as a new task as shown below. Running Tasks The task can be started by clicking the start button ( ). Note a task may run several hours depending on the scan configuration selected and network bandwidth as well as the resources of the OpenVAS server. A Full and fast scan should be completed about 10 minutes in the CVCLAB. A best practice is to create a schedule and assign the the schedule to the task. For example, a task can be run on every Friday night, and the results can be analyzed in the following morning. 5 of 9

6 After starting the task, its status changes to Requested. After this point, you may close the client (Don t do this!) and re-login periodically to check its status. The status of the task can be updated by clicking the refresh button ( ). Running Tasks When the task is completed, its status changes to Done as shown in the following picture. The Dashboard displays a summary of the scan. Cleary, the host has several high Threats that need to be addressed (the target has not been updated last three years!). 6 of 9

7 The details of the vulnerability report can be accessed by click on the details button ( ). After maximizing the report window ( ), all reports related to the task appear in the Report tab. 7 of 9

8 The details of a report can be accessed by double-clicking on the report. For example, OpenVS recommends disabling the discard service on the host Vulnerability assessment is continuous process. The network security administrators should frequently assess vulnerability of their system. Client-server vulnerability assessment tools simplify this process. In this activity, you have used OpenVAS. Nessus, a proprietary comprehensive vulnerability scanning program, is the most popular vulnerability scanner used 8 of 9

9 in the industry today. OpenVAS and Nessus share many common features as Nessus was created based on OpenVAS. All vulnerability scanners have a database of vulnerability tests, which are created and released by the vendors. The OpenVAS server in the CVCLAB performs over 25,000 tests in total. Therefore, a comprehensive vulnerability analysis may take several hours or days. Penetration Testing Assignment-Part 3 In the previous activities, you should have discovered the host Perform a vulnerability assessment of this host. In your report, include several recommendations to harden this host. Make sure to name your Task as (Initial Last Name) so that your instuctor can see your report. 9 of 9