Digital forensics is like trying to find a needle in a digital haystack.
It collects evidence from electronic devices, networks, and systems, helping investigators identify, preserve, and analyze evidence found in cybercrime. It figures out what was compromised and how a cybercriminal could have done it.
Many organizations use digital forensics tools to examine and investigate information technology systems after a security incident. These tools help digital forensics experts identify the root cause of a cyber attack and set preventive measures to avoid future incidents.
What is digital forensics?
Digital forensics is a branch of forensic science that deals with recovering, investigating, examining, and analyzing material in digital devices, especially in a cybersecurity incident.
Incident response teams and law enforcement agencies use it to investigate electronic evidence of a cybercrime.
Digital forensics definition
Digital forensics is a branch of forensic science that focuses on uncovering, interpreting, and preserving electronic data evidence while conducting a security incident investigation.
Digital forensics is also known as digital forensic science. As electronic devices are taking a substantial space in our modern lifestyles, knowingly or unknowingly, criminals or offenders use them in their malicious acts. This makes these devices solid pieces of evidence to support or refute an accusal in criminal and civil courts.
Criminal cases involve alleged lawbreaking and civil cases deal with contractual disputes between commercial parties. Digital forensics serves as a piece of solid evidence to examine both kinds of cases.
Digital forensic science also plays an important role in the private sector. Investigation agencies use it during internal corporate investigations or while probing unauthorized network intrusion incidents.
Using digital forensics analysis, these agencies can attribute evidence to suspects, confirm alibis, identify intent or authenticate documents. Many agencies leverage a company’s intrusion detection and prevention system to explore potential crimes while collecting and analyzing forensics.
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A brief history of digital forensics
Before the late 1970s, judicial authorities dealt with computer-related crimes using existing laws. In 1978, the Florida Computer Crimes Act recognized computer crimes for the first time. As criminal offenses related to computers grew in the following years, several laws were passed to deal with privacy issues, harassment, and copyrights.
In the 1980s, federal laws started incorporating computer offenses. The Federal Bureau of Investigation (FBI) started a Computer Analysis and Response team in 1984. Early members of this team were FBI officers who happened to be computer hobbyists.
In the 1980s, only a few digital forensics techniques programs were available. As a result, investigators performed live analysis and examined computers from within the operating system to extract evidence. Although investigators could get the evidence, there was a risk of modifying data, which would result in evidence tampering.
The early 1990s witnessed many new digital forensics programs, tools, and techniques to mitigate the risk of modifying data. Toward the late 1990s, advanced tools were developed as the demand for digital evidence grew.
Demand for new and basic investigation resources also increased. This demand sparked the creation of regional and local groups to help central forensic research units.
Various bodies and agencies began working to address the need for standardization and guidelines for digital forensics in the 2000s. Training researchers and investigators also received substantial attention in this decade.
Why is digital forensics important?
Just like a criminal leaves fingerprints and footsteps at the scene of a crime, a hacker leaves activity logs and metadata in a cybercrime. Digital forensic investigators analyze these electronic data to find the tools the attacker used, as well as their chosen method of launching a cyber attack.
Digital forensics finds the amount and nature of the damage due to cyber attack. Computer forensics experts play a major role in finding and preserving evidence related to the incident, which might become obsolete later.
They help the incident response team understand who the hacker was, how the hacker brought about the attack, and how much damage the attack did.
Below are some important aspects of digital forensics:
- Understanding a cyber attack’s cause and intent
- Maintaining security posture and backtracking the hacker’s steps to expose attack tools
- Preserving electronic evidence before it becomes obsolete
- Finding the source of data exfiltration or access
- Mapping logins using geolocation
- Detecting the duration of unauthorized access on the computer network
- Alerting steps needed to take to prevent further damage
- Providing intelligence on cybersecurity vulnerabilities in an organization and aiding patch management
- Helping business leaders make data breach disclosure decisions and inform relevant legal authorities
Digital forensics helps an organization even after an attack while dealing with its consequences. A digital forensic investigation highlights the path to compromised data, enabling organizations to clearly understand the impact of data breaches and to implement mitigation measures.
Below are some common areas where people find digital forensics useful:
- Intellectual property (IP) and internal investigations are typical corporate digital forensic use cases. They cover cases about IP theft, industrial espionage, IP misconduct, fraud, personal injury or death, or sexual harassment. Hardware and digital evidence help bring culprits to justice in courts.
- Data recovery is often seen as a subset of digital forensics. It helps to recover stolen or lost information in devices people use.
- Damage analysis is a common area where people leverage digital forensics to discover vulnerabilities and remediate them to prevent future cyber attacks.
- Criminal and private investigations employ digital forensic analysis to handle complex cases involving digital evidence such as those involving wire fraud or money laundering schemes.
- National security agencies use digital forensics to monitor email communications among suspected terrorists while constantly looking for any signs of a terrorist attack.
Types of digital forensics
Digital forensics is an ever-evolving field that ranges from simple data recovery to piecing together the identity of a hacker.
The scope and scale of the task are determined by what you are trying to accomplish. Are you trying to recover deleted files? Or are you trying to find out who hacked into your computer and stole all your information?
No matter what kind of digital forensic help you need, it is important to understand that there are different types, levels, and degrees of analysis.
Below are some common types of digital forensics that experts encounter in their investigations:
- Network forensics relates to detecting and monitoring network traffic to capture crucial evidence.
- Disk forensics collects evidence from digital storage devices such as USBs, CDs, hard drives, and DVDs.
- Wireless forensics is a part of network forensics that extracts evidence from wireless networking devices.
- Database forensics investigates databases and their relevant meta data to collect evidence.
- Email forensics handles the recovery and analysis of trashed data in an email.
- Malware forensics identifies malicious code and studies issues related to trojans and other viruses.
- Memory forensics investigates data in a computer’s cache memory or RAM and collects it as evidence.
Digital forensics process
There are five key steps to the digital forensics process: identification, preservation, analysis, documentation, and presentation.
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Identification
Identifying digital evidence ensures that investigators collect the right evidence and that it's not contaminated by other data sources.
Digital forensic experts identify the problem. They determine what kind of crime occurred, what types of devices may be involved, and how they can use those devices to solve the case. It involves identifying who or what is involved in the crime by looking at metadata related to the digital evidence (e.g., a video file). This allows investigators to determine whether or not the data itself is necessary for their investigation.
Preservation
Digital information can easily be altered or destroyed if mishandled, so it must be preserved to keep it safe from tampering. This maintains the integrity of the evidence.
Digital forensic examiners typically use image backup files while preserving the evidence. It's critical to ensure that the examiner doesn't leave any additional footprints while creating the image. Imaging software helps them to evidence tampering.
Access logs and data backups are dynamic as computers keep on receiving and changing information. Forensics examiners need to extract digital artifacts such as data packets, event logs, and containers and preserve them to prevent overwriting.
Analysis
This involves reviewing the identified evidence to determine the accuracy of the results. Analysts then look for any additional data that might help answer questions about the case.
They usually employ specialized digital forensics software that sorts through all of the evidence quickly and efficiently – finding out what happened as soon as possible. These software help them understand the incident and create events' timeline.
Documentation
Digital forensic analysts need to document their findings in court as evidence. Other investigators or supervisors within the organization may also request access to this information for their purposes.
Good digital forensics documentation covers critical information to draw insights and make an accurate conclusion.
Presentation
After documentation, experts summarize and present their findings to a court or any other investigating authority. Presentation assembles multiple angles of security incidents together, helping investigating bodies come to a conclusion.
These presentations follow protocols and include forensic methodology and analysis procedures with their explanation.
Benefits of digital forensics
It’s not enough to figure out how to shut down the hacker's access once they've gotten into a network. Digital forensic scientists have to know where the attack came from to close that door for good.
If that doesn’t happen, organizations will just be playing whack-a-mole with hackers, which compromises security every time new ones make it through.
Digital forensics gives cybersecurity experts the information they need to develop technology that keeps hackers out permanently. Once the expert knows how hackers got in, they create or program software that alerts administrators when an attack has taken place so they can prevent the hacker from gaining access.
Below are some common benefits of digital forensics:
- Prevents viruses. One of the most important uses of digital forensics is to identify how viruses enter a device or network. Digital forensics helps security experts understand the methods and tools hackers use to infiltrate a system. Using this knowledge, antivirus programs can focus on particular attack surfaces in order to prevent them.
- Recovers deleted information. In some cases, cybersecurity experts can recover files that users or hackers have deleted from their systems. This can be extremely useful if an employee has accidentally deleted important files or if the company needs to recover files from a compromised machine.
- Identifies vulnerabilities. Digital forensics helps security teams detect vulnerabilities in networks, devices, and websites that hackers use to gain access. This includes weak passwords and other security measures that don’t provide adequate protection against attacks.
Digital forensics challenges
Digital forensics presents unique challenges for investigators. These challenges are categorized into technical, legal, and resource.
Technical challenges
Technical challenges include identifying admissible evidence in court that may be useful to the investigation. Some data may be hidden or encrypted on a device, preventing experts’ access to it. Although encryption ensures data privacy, attackers also use it to hide their crimes.
Cybercriminals also hide some data inside the storage by using system commands and programs. They might as well delete data from the computer system.
In such situations, digital forensics tools can help recover this data from a device's free space or swap files. Some attackers also take advantage of the covert channel to hide the connection between them and the compromised system.
Below are some common technical challenges of digital forensics:
- Cloud storage making the investigation more complex
- The amount of time it takes to archive data
- Skill or knowledge gap
- Steganography, which is hiding information within a file while leaving its outer look the same
Legal challenges
Legal challenges include privacy concerns and data storage accessibility regulations. For example, some laws require companies to delete personal information within a certain time frame after an incident. A digital forensics tool can help recover this data so it’s not lost before an investigation occurs.
Some legal frameworks may not recognize every granular aspect of digital forensics. The cyber policy can fall short of the required qualifications and skills for identifying and proving evidence.
Below are some common legal challenges of digital forensics:
- Issues of privacy
- Admissibility in courts
- Electronic evidence preservation
- Authority to gather digital evidence
Resource challenges
With the internet and wide area networks, data is now flowing across physical boundaries. Electronic data has increased in volume, making it tricky for digital forensics examiners to identify original and relevant data.
Technology is also changing very rapidly. Due to this, it has become challenging to read digital evidence since new versions of systems aren’t compatible with old versions software that doesn’t have backward compatibility support.
Best practices for digital forensics investigations
Digital forensics experts should follow some standards and best practices while investigating a security incident.
Below are some best practices to ensure comprehensive investigations and credible evidence:
- Document the location and condition of everything before beginning investigations.
- Make copies of evidence and work on them instead of working on original files to avoid tampering with them.
- Be systematic and comprehensive with analysis and collect evidence to support or refute a hypothesis with multiple possible theories.
- Follow standard procedures to handle evidence and preserve it without alteration or deletion.
- Prepare investigation documentation with detailed, clear, and factual data.
- Avoid technical jargon as much as possible and create an appendix for additional information.
- Summarize investigation documentation without any bias and validate findings with forensics interviewers in critical cases.
- Adhere to regulatory guidelines like ISO/IEC 27037:2012 that identify, collect, and preserve digital evidence.
- Be ethical while investigating an incident and avoid divulging any inadvertently acquired attorney-client information without the attorney’s consent or judge’s order.
Top 5 digital forensics tools
Digital forensics tools help incident response teams aggregate security information from hardware, network logs, and network files to detect the possible cause of a security breach. The forensics teams conduct an in-depth analysis of systems and facilitate incident response processes.
To qualify for inclusion in the digital forensics software list, a product must:
- Conduct email, internet, file, memory, and hardware security analysis
- Perform analysis after indexing aggregated security information
- Automate and outline security investigation workflows
- Outline security vulnerabilities in investigative reports.
*This data is collected from the G2’s digital forensics software category on April 14, 2022. Some reviews may be edited for clarity.
1. IBM Security QRadar
IBM Security QRader identifies, understands, and prioritizes the most crucial threats to a business. It offers complete threat detection and response solutions that eliminate threats faster.
What users like:
“The product helps to identify threats or vulnerabilities hiding in the system and to find a quick solution to them. The rules and offenses can be used to work on threat secure policy. The IBM app for integration of many security information and event management (SIEM) tools to gather logs and work on them is top-notch.”
- IBM Security QRadar Review, Rajesh M.
What users dislike:
“The major issue is with connectors of legacy applications. It needs to work at par with the competition or excel as it is found wanting in the security orchestration, automation, and response (SOAR) platform or what you may call next-generation security operations center (SOC). I also felt it was wanting in the data management domain, be it with structured or unstructured data. Cost-wise as well, it is a huge overhead.”
- IBM Security QReader Review, Darshan C
2. FTK Forensic Toolkit
FTK Forensic Toolkit is a computer forensics software that scans hard drives, locates deleted emails, and scans a disk for text strings to crack encryption. It provides an aggregation of the most common forensic tools to investigators.
What users like:
“We chose it as our computer forensics tool for our higher education system component office because of its ease of use, fast learning curve, and comprehensive visualization. FTK was perfect because it is quick to learn, and it gathers a huge amount of information. The install goes smoothly, and the training is top notch.”
- FTK Forensic Toolkit Review, Pinkee H.
What uses dislike:
“Some aspects of the search capability you need to be aware of upfront, or it will significantly affect your searches.”
- FTK Forensic Toolkit Review, Joseph S.
3. ExtraHop
ExtraHops’ cyber defense platform detects and responds to advanced cyber threats. It allows security professionals to detect malicious behavior and investigate any security incident with confidence.
What users like:
“Pretty easy to set up once you know the basics of spanning your traffic correctly and even easier since it has a dedupe engine. It has a user-friendly interface, which presents clearly the security detection and network analytics for the security and network team.
As a network specialist, I enjoy network health monitoring through advanced Transmission Control Protocol (TCP) analysis and protocol errors. Extrahop 360 has a powerful engine that let us do fast searches and keeps a large amount of metadata so we can go back in time.”
- ExtraHop Review, François G.
What users dislike:
“Extrahop has an avenue it needs to deep dive into immediately, and that's inspecting, categorizing, risk scoring, and using external database data for IIoT/IoT devices. Currently, it can see the traffic on the wire, but the behaviors and risks behind IoT devices will overtake the standard known IT hardware in a few years.
Not necessarily Extrahop's fault as it’s a problem with any of these solutions, but aggregating traffic in a large enterprise is not only challenging but an expensive endeavor. As a work-around, we use packet brokers to decrease the traffic flows to those we care about to ensure we don't massively oversubscribe the devices.”
- ExtraHop Review, Travis S.
4. Parrot Security OS
Parrot Security OS is a Linux distribution based on Debian with a focus on security, privacy, and development. It provides a suite of penetration testing tools to be used for attack mitigation, security research, and forensics.
What users like:
“One of the main advantages offered by this distribution is that it provides good support for the updates of its different tools. There is a strong community that periodically reviews the latest packages of each of the tools.
In addition, the best tools for performing security audits are pre-installed out-of-the-box, especially from the offensive point of view, with the objective to discover and exploit vulnerabilities in an organization's infrastructure.”
- Parrot Security OS, Jose M Ortega
What users dislike:
“Sometimes parrot OS gets slow when you use any heavy intensive app because it doesn't support a variety of graphic cards natively, but you can also make it work after some changes.
Sometimes it has compatibility issues with peripheral devices such as USB wireless cards and token devices.”
- Parrot Security OS, Indrajeet S.
5. Cyber Triage
Cyber Triage offers automated incident response software that investigates vulnerable endpoints. It pushes its collection tool over the network, gathers relevant data, and analyzes it for malicious or suspicious activity.
What users like:
“User friendly solution that saves time because it is agentless, fully automated, and focused on triage principles. Doesn't require a middle man to process information returned by the utility, as all is processed in real-time.”
- Cyber Tirage Review, Indars S.
What users dislike:
“It, being an agentless system, tracks end user activity through user accounts. This means it gets all account data and analyzes them remotely instead of on-prem.”
- Cyber Triage Review, Poonam K.
Protect your systems
The importance of digital forensics has grown in recent years as the world has become increasingly reliant on technology to record our actions, thoughts, and memories in the form of information stored on computers.
Electronic fingerprints are everywhere. In any cybercrime, this electronic evidence serves as a crucial instrument in supporting or refuting a hypothesis in a court of law. Digital forensics discovers this evidence and sets preventive measures to prevent similar cyber crimes in the future.
Learn more about vulnerability management so you can fix security weaknesses in your systems and networks.
Sagar Joshi
Sagar Joshi is a former content marketing specialist at G2 in India. He is an engineer with a keen interest in data analytics and cybersecurity. He writes about topics related to them. You can find him reading books, learning a new language, or playing pool in his free time.
