Detect evidence of break-in attempts with host-based intrusion detection systems
All in One
Instead of three tools that complement one another, some solutions combine all three functions into a single tool. Whether or not this approach is superior is very much a question of taste. Notable all-in-one solutions include Samhain [10] and OSSEC [11]. Both of these all-in-one tools offer an agent mode that runs sensors on remote systems, which then transfer their data to a central computer for evaluation.
If you are paranoid and have sufficient free time to read all the email, you will be happy to hear that multiple HIDS tools running in parallel do not get in each other's way. In other words, you can run a combination of Tripwire, AIDE, AFICK, Samhain, and OSSEC on a single computer and let the systems monitor one another. But some caution is advised: Updates that arrive at the same time can easily send the system into an infinite loop.
Look online for detailed HowTo information on Samhain [12] and OSSEC [13]. Using these tools is not exactly rocket science if you know how the components work.
Having said this, each additional line of code adds the risk of security-critical programming errors. For example, OSSEC 2.7 to 2.8.1 had a privilege escalation problem in June 2015: CVE-2015-3222 [14]. Version 2.8.2 was the first to provide a working patch. Whatever tool and version you use for your network, the task of managing your HIDS should include watching for security updates: You will not want your security tools to cause new vulnerabilities.
Tracking Down the Thief
Host-based intrusion detection systems come in many varieties, with features that often complement one another, and pre-built packages are available that combine all of the required functions. HIDS logs give admins who have fallen victim to a successful attack important information that lets them understand the attacker's actions, plug the gaps, and possibly even bring the evildoer to justice.
Many tools reach their performance limit when the attacker has root privileges and sufficient time to disable security mechanisms and clean up their tracks. Because an HIDS by design only detects the results of an attempted attack, it can only be one building block in the overall security architecture. A network intrusion detection system, firewalls, restrictive user rights, regular security audits of your systems, and efforts to raise your users' security awareness complete the puzzle.
Infos
- Locard's principle: https://en.wikipedia.org/wiki/Locard%27s_exchange_principle
- Tripwire: http://sourceforge.net/projects/tripwire/
- AIDE: http://aide.sourceforge.net
- AFICK: http://afick.sourceforge.net
- HowTo Enable Core Dumps: http://en.linuxreviews.org/HOWTO_enable_core-dumps
- Logsentry: http://sourceforge.net/projects/sentrytools/files/logcheck%201.x/logcheck-1.1.1/
- ClamAV: http://www.clamav.net/index.html
- Chkrootkit: http://www.chkrootkit.org
- RKHunter: http://rkhunter.sourceforge.net
- Samhain: http://www.la-samhna.de/samhain/
- OSSEC: http://www.ossec.net
- Samhain manual: http://www.la-samhna.de/samhain/MANUAL-2_4.pdf
- OSSEC manual: http://ossec-docs.readthedocs.org/en/latest/manual/installation/index.html
- CVE-2015-3222: http://www.openwall.com/lists/oss-security/2015/06/11/1
« Previous 1 2
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
TUXEDO Computers Unveils Linux Laptop Featuring AMD Ryzen CPU
This latest release is the first laptop to include the new CPU from Ryzen and Linux preinstalled.
-
XZ Gets the All-Clear
The back door xz vulnerability has been officially reverted for Fedora 40 and versions 38 and 39 were never affected.
-
Canonical Collaborates with Qualcomm on New Venture
This new joint effort is geared toward bringing Ubuntu and Ubuntu Core to Qualcomm-powered devices.
-
Kodi 21.0 Open-Source Entertainment Hub Released
After a year of development, the award-winning Kodi cross-platform, media center software is now available with many new additions and improvements.
-
Linux Usage Increases in Two Key Areas
If market share is your thing, you'll be happy to know that Linux is on the rise in two areas that, if they keep climbing, could have serious meaning for Linux's future.
-
Vulnerability Discovered in xz Libraries
An urgent alert for Fedora 40 has been posted and users should pay attention.
-
Canonical Bumps LTS Support to 12 years
If you're worried that your Ubuntu LTS release won't be supported long enough to last, Canonical has a surprise for you in the form of 12 years of security coverage.
-
Fedora 40 Beta Released Soon
With the official release of Fedora 40 coming in April, it's almost time to download the beta and see what's new.
-
New Pentesting Distribution to Compete with Kali Linux
SnoopGod is now available for your testing needs
-
Juno Computers Launches Another Linux Laptop
If you're looking for a powerhouse laptop that runs Ubuntu, the Juno Computers Neptune 17 v6 should be on your radar.