user manual

with the word [SPAM]. An email header (X-BitDefender-Spam: Yes/No) is added to all

emails to ease the client-side filtering.

11.6. Perform a network security audit

Beside its anti-malware, data recovery and mail filtering capabilities, LinuxDefender comes

with a set of tools that perform an in-depth host & network security audit. Forensics analysis

of compromised systems is also possible using the security tools included into LinuxDefender.

Read this small tutorial to learn how you can start a quick security audit of your hosts or net-

works.

11.6.1. Check for rootkits

Before start looking for security issues on networked computers, first be sure that the

LinuxDefender host is not compromised. You can perform a virus scanning of installed hard-

drives, as shown in Scan for viruses tutorial or you can scan for Unix rootkits.

First, mount all your hard-disk partition, double-clicking their desktop icons or by using mount

command in the console. Then double click the ChkRootKit icon to check the CD content or

launch the chkrootkit command in the console, using -r NEWROOT parameter to specify the

new / (root) directory of the host.

# chkrootkit -r /dev/hda3

If a rootkit is found, chkrootkit will show the finding in BOLD, using capital letters.

11.6.2. Nessus - the Network Scanner

What is Nessus. “ Nessus is the world's most popular open-source vulnerability scanner used

in over 75,000 organizations world-wide. Many of the world's largest organizations are obtaining

significant cost savings by using Nessus to audit business-critical enterprise devices and applic-

ations. ”

Nessus can be used to remotely scan your network computers against various vulnerabilities.

It also recommends some measures to take to mitigate security risks and to prevent security

incidents.

Double-click the Nessus Security Scanner desktop icon or run startnessus from a terminal.

Wait until the following window is shown. Depending on your hardware resources, it may

take up to 10 minutes for Nessus to load, along its more than 5000 plugins containing vulner-

ability databases. Use knoppix user and knoppix password to log in.

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BitDefender

Rescue CD

LinuxDefender howto