Digital Forensics and Incident Response (DFIR)

5 min. read

Digital forensics and incident response (DFIR) is a rapidly growing field that demands dynamic thinking and a novel approach. Combining digital investigative services with incident response expertise is critical to manage the growing complexity of modern cybersecurity incidents.

What Is Digital Forensics and Incident Response (DFIR)?

Digital forensics and incident response are branches of cybersecurity that involve identifying, investigating, containing, remediating and potentially testifying related to cyberattacks, litigations or other digital investigations.

DFIR services combine two major components:

  • Digital forensics: This investigative branch of forensic science collects, analyzes and presents digital evidence such as user activity and system data. Digital forensics is used to uncover the facts about what happened on a computer system, network devices, phones or tablets and is often employed in litigations, regulatory investigations, internal company investigations, criminal activity and other types of digital investigations.
  • Incident response: Incident response, similar to digital forensics, investigates computer systems by collecting and analyzing data. This is done specifically in the context of responding to a security incident, so while investigation is important, other steps such as containment and recovery are weighed carefully against each other while responding to an incident.

History of Digital Forensics and Incident Response

In the early days of digital forensics and incident response, while the goals of matters pertaining to each may have differed, the tools, process, methodology and technology used were, in many ways, similar or identical. Historically, the method of collecting data for DFIR matters was often to collect forensic images of user’s computers and company servers as well as copies of log data, where stored separately. These large sets of data were then analyzed using investigative tools to convert and interpret data on the computer systems into information that could be understood by computer experts, who could then work to identify potentially relevant information.

Digital forensic matters generally still follow the same process as they did historically because of the deep-dive level of scrutiny required to collect and analyze data to then present in court or to a regulator. However, in modern-day incident response matters, the tools and approach have evolved to better meet the differing goals of incident response by leveraging ever-evolving technology.

Today, incident response is often performed using EDR or XDR tools that give responders a view into data on computer systems across a company’s environment. This is often accessible immediately or very quickly across dozens, hundreds or even thousands of endpoints. This rapid access to useful investigative information means that in an incident, responders can start getting answers about what is happening very quickly even if they do not already know where in the environment they need to look. Such tools can also be used to remediate and recover by identifying, stopping and removing malware or other tools used by a threat actor in the environment.

Digital forensics generally seeks to collect and investigate data to determine the narrative of what transpired. Incident response generally seeks to investigate, contain and recover from a security incident. They share a history as well as many tools, processes and procedures. In addition, a matter involving responding to an incident today may end up in litigation in the future. Because of the history, the overlap in tools/process, and because an incident response matter may lead into a digital forensics matter or vice versa, these two types of services are commonly still described as one group of services: digital forensics and incident response (DFIR).

Digital Forensics and Incident Response Challenges

As computer systems have evolved, so too have the challenges involved in DFIR. There are several key obstacles digital forensics and incident response experts face today.

Digital Forensics Challenges

  • Scattered evidence: Reconstructing digital evidence is no longer reliant upon a single host; it is scattered among different physical or virtual locations. As such, digital forensics requires more expertise, tools and time to thoroughly and correctly gather and investigate threats.
  • Fast pace of technology: Digital devices, software programs and operating systems are constantly changing, evolving and growing. With this fast pace of change, forensic experts must understand how to manage digital evidence in a large variety of application versions and file formats.

Incident Response Challenges

  • Growing data, dwindling support: Organizations are facing more and more security alerts but cannot find the cybersecurity talent required to address the volume of information and ultimately the relevant threat data. Increasingly, organizations are turning to DFIR experts on retainer to help bridge the skills gap and retain critical threat support.
  • Increased attack surface: The vast attack surface of today’s computing and software systems makes it more difficult to obtain an accurate overview of the network and increases the risk of misconfigurations and user error.

These challenges call for DFIR experts to help support growing alerts and complex datasets and take a unique and flexible approach to threat hunting within modern, ever-evolving systems.

Digital Forensics and Incident Response Best Practices

A robust DFIR service provides an agile response for businesses susceptible to threats. It gives you peace of mind that expert teams with vast knowledge of cyber incidents will respond to attacks quickly and effectively.

Digital Forensics Best Practices

The success of DFIR hinges on rapid and thorough response. It’s crucial that digital forensic teams have ample experience and the right DFIR tools and processes in place to provide a swift, practical response to any issue.

Expertise in digital forensics has a number of benefits, including the ability to discover the cause of an incident and accurately identify the scope and impact. Employing the right investigative tools will ensure prompt discovery of the vulnerabilities that led to an attack or unintentional exposure.

Incident Response Best Practices

Incident response services are tailored to manage an incident in real time. IR best practices include preparation and planning as well as timely, accurate and reliable mitigation and response to reduce reputational harm, financial loss and business downtime.

Combined, digital forensics and incident response best practices include determining the root cause of issues, correctly identifying and locating all available evidence/data, and offering ongoing support to ensure that your organization’s security posture is bolstered for the future.

What Are the Steps of the DFIR Process?

The Palo Alto Networks Unit 42 DFIR solution is uniquely driven by threat intel, and every responder on our team is an expert equipped with cutting-edge tools and techniques. Our DFIR process consists of two steps that work in tandem.

Digital Forensics Process

  • Identify: This is the first step is to identify all evidence and understand how and where it is stored. This step requires deep technical expertise and analysis of all manner of digital media.
  • Preserve: Once the data has been identified, the next step is to isolate, secure and preserve all data until the end of the investigation, including any regulatory or litigation related inquiries.
  • Analyze: The data is then reviewed and analyzed to draw conclusions on the evidence found.
  • Document: At this stage, the relevant evidence is used to recreate the incident or crime for a thorough investigation.
  • Report: At the end of the process, all evidence and findings are presented according to forensics protocols, including the analysis methodology and procedures.

Incident Response Process

  • Scope: The first goal is to assess the breadth and severity of the incident and identify indicators of compromise.
  • Investigate: Once the scope is determined, the search and investigation process begins. Advanced systems and threat intelligence are used to detect threats, collect evidence and provide in-depth information.
  • Secure: With individual threats addressed, there still needs to be an identification of security gaps and ongoing monitoring of cyber health. The secure stage involves containing/eradicating active threats that were identified from the investigation and closing any identified security gaps.
  • Support and Report: Each security incident is closed out with customized reporting and a plan for ongoing support. We examine the overall organization and provide expert advice for next steps.
  • Transform: Finally, identify gaps and advise on how to effectively harden areas of weakness and mitigate vulnerabilities to improve security posture of the organization.

Each process and step must be optimized to ensure a speedy recovery and set the organization up with the best chance of success in the future.

Unit 42’s Incident Response consultants have experience performing IR in traditional computing and in all major Cloud Service Provider environments. Our DFIR-specific methods can help you recover from security incidents with rapid scoping, access, investigation and containment specific to the detected threat. We have built playbooks for the top cyber incidents our customers face, and we provide tabletop exercises to familiarize them with every phase of the IR playbook. Learn more about how Unit 42 DFIR services can help protect your organization.