There's a lot we know about advanced persistent threats, but there's a lot we don't know.
This is due in large part to the complexity of the attacks and the stealth of the attackers. Our knowledge about APTs is growing, but, unfortunately, that's because the attacks themselves are growing in frequency. Criminals using APTs want data, so the more valuable an organization's data, the more likely it is to be targeted.
Government agencies and organizations in industries such as finance, energy, IT, aerospace, and chemical and pharmaceuticals are the mostly likely to be the victims of APT infections, as are those involved in international trade. Users and organizations with access through business relationships to valuable data, such as smaller defense contractors, are also beginning to be targeted.
And the use of watering hole attacks may be heralding a change in tactic to mass infections, which are then sifted for any potentially interesting targets. Criminals are less likely to target organizations running critical infrastructure, but attempted APT-type attacks by hactivists and nation-states are on the increase. Any organization running industrial control systems linked to the Internet is at risk.
Administrators of some systems may be unaware that their systems are connected to the Internet, while systems installed some years ago, when cybersecurity was less of an issue, may not be adequately protected from attack.
What Is an APT? Though the term originally referred to nation-states engaging in cyber espionage, APT techniques are also being used by cybercriminals to steal data from businesses for financial gain. What distinguishes an APT from other threats is that it is targeted, persistent, evasive and advanced.
Unlike the majority of malware, which randomly infects any computer vulnerable to a given exploit, APTs target specific organizations with the purpose of stealing specific data or causing specific damage.
The Conficker worm, for example, used many advanced techniques but did not target a particular organization. It infected millions of computers in more than 200 countries. In contrast, Stuxnet was designed to target a certain type, a certain brand and a certain model of control system.
To achieve their objective, those developing an APT must find vulnerabilities within a target's infrastructure, evaluate the security controls protecting it, determine how to deliver the attack and exploit the vulnerability, compromise the target network, gain access to privileged hosts, find the target data and then extract it -- all without being detected. This requires enormous amounts of research, and the entire process may take months or even years.
A key difference between most malware and an APT is its ability to persist -- that is, to evade detection by network security controls while still collecting and extracting data. The ingenious methods used in the past show the in-depth knowledge of the attack developers. In many cases, developers use unknown zero-day exploits so there are no antivirus signatures available to provide protection.
To learn more about the nature and behavior of today's APTs -- and to find out what you can do to protect your organization -- download the free report on APTs.
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