As attack techniques progress, businesses need more than the existing methods of protection they've been using for years, such as signature-based technologies.
"Signatures of malware are like the TSA trying to use a photograph and fingerprint of every person in the world. In theory, it will work. But in this case, the fingerprint and the face keep changing," says Srinivas Kumar, co-founder and CTO of Taasera, a startup that offers detection techniques based on application behavior, rather than characteristics.
Security tools based on application behavior detection methods get rid of this problem. Rather than comparing what the code in an application looks like with a blacklist, as many traditional AV and endpoint security products do, behavior-based tools analyze how the application interacts with the system to assess whether the application is benign or malicious.
Behavioral detection methods try to deal with the problem of malware variants and offer some protection from zero-day attacks. The systems watch behavior and string together not just one behavior but multiple behaviors. "Did it open up the registry? Well, that by itself isn't so bad," says Brian Laing, director of U.S. marketing and products for AhnLab. "Did it write to the registry? That by itself isn't necessarily bad, either. Did it write to the run-once registry key? That's bad."
But even these methods require an understanding of the tactics attackers might use. Too many of the security industry's tools still rely on some kind of prior knowledge -- whether signatures, tactics, or URLs to avoid. For example, deep packet inspection generally uses a library or list of URLs known to be bad. And whitelisting technologies might depend on a cloud-based list of allowable functions to run. "That's all prior knowledge -- it's static and needs to be updated," says John Prisco, CEO of Triumfant, a malware analytics firm. Algorithmic-based tools that assess how a virus acts rather than what the code looks like are needed for a sustainable long-term anti-malware effort. "If you're not including more algorithmically based tools in your strategy, you're really fooling yourself into having this false sense of security," he says.
Businesses also must get serious about protecting their internal networks, says Rapid7's Moore. We've known for a decade that hardening networks with firewalls isn't enough, yet companies still leave their networks flat and unprotected inside the firewall. "The security of the internal network really starts to matter just as much as the external," Moore says.
Companies must segment high-value assets away from heavily trafficked parts of the network and institute more secure authentication and password management on endpoints and network assets. These steps create roadblocks to prevent the compromise of one internal machine from spreading to others.
For example, Moore points to a recent attack against oil company Saudi Aramco, in which 30,000 endpoints were compromised and damaged by hacktivists. There's been speculation that the victims shared passwords across all the desktops, something that's too common. "It's because of those kinds of fundamental security problems that these attacks are still happening -- and why people have to worry about malware on corporate networks," Moore says.
Segmentation doesn't have to be limited to the network. Many organizations are using virtualization and application sandboxing to provide a protective bubble against execution of malicious code. Applications run in a virtualized, contained layer above the actual system layer, creating a sandbox that keeps bad applications away from the root processes in the system.
Sandboxing isn't unassailable. Attackers can find vulnerabilities in the sandbox's parent process or in the operating system itself that let them neutralize the containment functionality, says Chris Valasek, senior security research scientist for application testing vendor Coverity. If hackers find a flaw in either one and run an exploit that lets them tinker with sandbox settings, they can allow their malware payload to escape the sandbox and execute functions at the system level rather than in the container.
"Windows kernel vulnerabilities are quite popular for privilege escalations because if exploited, they give the user total control of the system," Valasek says.
Malware is a moving and growing threat, and no one defense mechanism is going to neutralize it and completely protect businesses. A layered, integrated approach is most effective, one that uses a range of the different defense methodologies to keep wily attackers at bay. This "defense in depth" approach is more likely to be able to stand up to future malware no matter where the bad guys take the technology. That's a key advantage given that the scariest exploits are the ones we don't know about yet.
Sidebar
How Crimeware Kits Work
Crimeware kits are designed by professional hackers to automate the creation and propagation of malware.
They're sold to criminals who don't have the technical chops or the time to create their own malware. Operating under ominous names such as Blackhole, Cool EK, Nuclear Pack and Red Hole, these kits consist of ready-made programs that infectwebsites with malcode that automatically downloads from the website onto a site visitor's machine (referred to as a "drive-by download"). It then seeks out a specific vulnerability and exploits it. Many offer turnkey software-as-a-service subscriptions, giving users access to already infected sites and frequently updated exploit payloads. Crimeware kits cost anywhere from $300 up front to $10,000 a month as a service. Attackers use them to carry out malware campaigns that target specific user populations and vulnerabilities.
Malware kits were used liberally during last year's election, luring people to infected sites through election-related phishing messages. Criminals sent messages that looked like newsletters with links to CNN news articles that actually redirected readers to malicious links where the kit could take over and infect victims' machines.
-- Ericka Chickowski