Network forensics is a branch of digital forensics. Inherently, network forensics is dynamic as it involves monitoring, analyzing, potentially capturing, and investigating information transiting the network environment. This contrasts with other digital forensics such as “data at rest” analysis which is performed on stored data captured and held on tape, disk, or other means. One way of viewing network forensics is like a “security camera” for the network link being monitored, which enables IT teams and investigators to view the unauthorized access or cybercrime from start to finish. In this blog we explore the importance and challenges of network forensics.
What is the importance of network forensics?
The heightened threat environment and expanding attack surface are increasing the probability of exploitation of networks by hackers. Given this, the criticality of network forensics continues to grow. For example, tools such as firewalls are designed to allow legitimate traffic to pass while blocking activity to or from specific IP addresses, networks, or ports based on defined rules. Unfortunately, there are protocols and other techniques that enable malefactors to sometimes circumvent these defenses.
The other huge area of exposure is insider threats, whether from authorized individuals that have had their access compromised—such as their passwords stolen—or by rogue staff seeking sensitive organizational IP or stakeholder/customer data for illicit use. In either case, this is yet another path that potentially enables bad actors to move freely across the network undetected.
Observing this malicious activity (near) real-time allows IT teams to take a more proactive posture by serving as threat detection and prevention. The sooner the behavior is spotted, the easier it is to limit possible damage. In this case, the “security camera” would be capturing the action as it occurred or very shortly thereafter.
The value of network forensics
Even if used only after a security event has transpired, network forensics is still incredible valuable. Why? Because effective incident response and subsequent recovery hinges on quantifying the scope and impact of the breach. Only with this information—provided by network forensics and captured for post event analysis—can the situation be first contained and then eliminated. Recovery can begin only at this point. In this scenario, the “security camera” abilities of network forensics would serve as direct evidence after the “crime” has occurred.
In either circumstance, whether during or after the incident, network forensics—assuming the data is captured—can aid in regulatory compliance and by providing legally admissible evidence. Network forensics can also assist in better understanding attack vectors, enabling the reinforcement of existing security measures or the addition of new ones. Lastly, network forensics can help IT teams with risk management and mitigation, enabling organizations to prioritize and then optimally address security problems with available resources.
The challenges of performing network forensics?
The obstacles to effective network forensics are many. First, the speed of networks and the volume of data—the latter tied to the number of endpoints, big data analysis, and popularity of bandwidth hungry services such as streaming. The technical challenges of simply keeping up with the torrent of packets is mind boggling. Even if that is achieved, you still need to analyze the information comparing it to known threat signatures or if a zero-day event using other techniques such as behavioral methods to detect unauthorized actions. The growing use of encryption complicates the effort as does escalating data privacy regulations and legal constraints.
How network forensics complements other security measures
Based on the conversation so far, the value of network forensics is hopefully clear. When—not if—existing security tools and processes fail, network forensics can aid in containment and recovery, serve as a means to understand the new attack vector and then used, to eliminate future attempts using that technique. Network forensics can also be a source of valuable data to feed to existing solutions, expanding their visibility and enhancing effectiveness. In addition, processes and polices can be refreshed to better optimize resources whether staff of IT budgets.
In summary
To the extent possible, organizations should consider network forensics as a key part of their larger cybersecurity defense strategy. Whether bolstering real-time security activities or serving as after-the-incident “damage control” to help contain, clean-up, and then recover network forensics can greatly improve cybersecurity posture by strengthening existing tools and enhancing processes/polices to achieve peak IT service delivery.
How CyberScope can help
CyberScope is designed to provide comprehensive visibility at the edge network, including the ability to perform line-rate 10Gb packet capture. As such, it can serve as a valuable source of traffic at the perimeter where many breaches often begin.
