Your Company Has Just Been Attacked By Malware, Now What?

Malware Attack

A Verizon report shows what anyone working with critical infrastructure knows already – that this strategy of defending the endpoint alone is not working. While there is a lot of low sophistication attacks happening every day – 78 per cent classed as low difficulty by Verizon – that means that almost a quarter must be sophisticated and targeted.

No security plan is perfect, yet many organisations still do not factor the inevitability of compromises into their overall defense strategies – instead focusing on what must be done to keep every conceivable type of threat at bay. This is reinforced by a reflexive assumption that new technologies can close every gap attackers need. Yet, research consistently reveals why some attacks can routinely bypass updated layers of network and endpoint security products. More than ever, preparing for an attack must include sealing-off damage and more rapidly restoring systems to trusted states.

Modern threats demand a modern response strategy along the full threat lifecycle. Let’s take a closer look at key considerations for updating your security and incident response strategy with the objective of gaining visibility and control of advanced malware for better protection.

Shoring up defences

Any advanced malware response strategy must start with detection and blocking. In order to have effective detection and blocking, without a lot of “noise,” you need a baseline of information about what’s on your network in order to defend it – devices, operating systems, services, applications, users, content and potential vulnerabilities.

Malware detection, the ability to identify files as malware at the point of entry and remediate accordingly, combined with implementing access control over applications and users, is also important. Not only do these measures help you to take steps to reduce the surface area of attack, but with the right informational context, detection may also indicate that your business is in the bull’s-eye of a targeted attack. Unfortunately, this first line of defence is where many security and response strategies begin and end.

What’s needed is the ability to roll back time against would-be attackers and understand the context of a detection within a broader community of malware and whether it is widely distributed or unique, and meant specifically for you. Retrospective detection is a means to continuously look back and compare any program against the latest threat intelligence for detection, effectively eliminating a key dimension of attack – time.

A lattice of detection technologies that collectively work together, leveraging context from each other to improve detection at the point of entry and retrospectively on the network and host systems, is essential when updating your response strategy.

Identifying the target(s)

Still, the best threat detection and blocking only goes so far. When an attack does happen you need to be able to identify ‘Patient Zero’, the malware origination point. From there, visibility to identify affected systems, the application that introduced the malware, the files that are causing it to spread and which systems are affected enables you to address the infection at the root and avoid re-infection.

The ability to understand how the malware is communicating within and outside the network, system to system, application to application and out to command and control servers and other malicious sites provides even more insight to identify origination points, control affected systems and stop reinfection. When you’re under siege, finding affected systems quickly is the key to breaking the malware lifecycle.

Enemy reconnaissance

When an attacker successfully circumvents traditional security technologies, your incident response plan kicks in. At that point, chances are you’re in firefighter mode without the time, nor a PhD in forensics, to delve into volumes of data and sophisticated analytics. Use of Big Data analytics to identify fundamental behavioural characteristics of the malware will help you to quickly understand the threat. Visibility into how the malware affects other files it has either interacted with or dropped on the system is also essential.

And the old adage “one bad apple can spoil the bunch” applies here. Understanding system to system relationships is critically important. Has the malware already begun communicating with other systems? If so, then the attacker may have already established a foothold on other systems by leveraging escalated privileges gained on the original affected system. With this level of access, the attacker could leave the original infected system and permeate other systems, thus becoming invisible to traditional detection methods until the damage is done. Gaining deeper insight into the threat and its trajectory will help you defeat it.

Gaining the upper hand

With greater visibility and better protection, you can start to gain control and remediate. Detection and blocking combined with identifying affected systems ensures you start from a position of strength, eradicating the malware so you don’t lose ground. Updating protections based on the latest threat intelligence as well as constraining and eliminating attack vectors with application control enables you to further reduce risk. Understanding file behaviour and its path can help you minimize the impact of an attack and recover.

You also need control over grey areas, and in the case of advanced malware there’s a lot of grey area between ‘known good’ and ‘known bad’ files. You need to be able to block suspicious files or continue to track and analyse them against real-time threat intelligence. If security data indicates that a suspicious or unknown file is actually malware, retrospective remediation enables you to remove it. But control can’t stop at the network. Network-based protection should work in lock-step with device protection to ensure a comprehensive response and remediation across the full lifecycle of threats.

Effective advanced malware response requires visibility and control across the entire IT environment and along the full threat lifecycle, to not only identify and stop the spread of malware but also minimise the risk of reinfection. With the ability to detect and eradicate malware quickly and effectively you can be confident your security and incident response strategy is up to today’s challenge.

Leon Ward

Leon is a field product manager for Sourcefire. Prior to joining Sourcefire, Leon was involved in the design and development of open source (OSS) Intrusion Prevention Systems. Leon applies his strong background in UNIX security and protocol analysis to overcome the challenges of network security monitoring in the enterprise, specifically in the areas of network intrusion detection, threat mitigation, event analysis and vulnerability assessment. In the little spare time Leon finds, he is the lead contributor to the open source network traffic forensics project OpenFPC (Open Full Packet Capture).