Incident response: what is the DFIR approach?
In 2024, 47% of French businesses suffered at least one significant cyber attack. At the same time, the number of incidents handled by Anssi rose by 15%. At a time when attackers' modus operandi are becoming increasingly complex, orchestrating an effective response to security incidents is a constant challenge.
Against this backdrop, a growing number of companies are relying on DFIR (Digital Forensics and Incident Response), an approach that combines forensic analysis and incident response. In this article, you'll find out how DFIR can enable your business to respond quickly and effectively to security incidents, while proactively strengthening your level of protection.
The DFIR, an approach to understanding and countering cyber attacks
When you're faced with a cyber attack, it's crucial to react in real time to contain it and prevent it from disrupting your business. At the same time, you need to gather information about the incident in order to understand its origins, and pass this information on to the police so that they can identify the perpetrators. The DFIR approach responds to these different imperatives in three stages:
1. Collecting digital evidence:
When an incident occurs, the first step is to gather all available information about the attack and collect digital evidence, i.e. the traces left by the attackers (malware signatures, deleted files, access logs, etc.). This information can then be handed over to law enforcement agencies in order to identify and arrest cybercriminals. They can also be used as part of a criminal investigation.
2. Forensic analysis:
The aim of this second stage is simple: to reconstruct the chronology of the incident in order to analyse the attackers' modus operandi. This analysis first enables you to identify the initial vector of the attack (phishing, application vulnerability, unauthorised access, etc.). It also helps you to understand what attackers are doing inside your IS, and to detect potentially compromised systems or data. This information is then used by your teams to address the vulnerabilities exploited in the incident and strengthen your level of protection.
3. Incident response:
Each incident is unique, and requires a tailored response depending on its severity and potential impact on critical infrastructures. The aim of this third stage is to contain the threat, eliminate the malicious elements identified (malware, unauthorised access, etc.) and restore your compromised systems. Depending on the situation, it may be necessary to isolate a network segment, temporarily suspend certain services or reset user access.
The advantages of the DFIR approach
The DFIR approach offers a number of advantages in terms of cybersecurity:
- Reduced impact of security incidents: applying the DFIR approach means you can react quickly and effectively to attacks. In concrete terms, an accelerated response to incidents reduces the damage caused to your IS, the disruption to your business and the financial costs incurred by an attack.
- Streamlined investigation: the DFIR makes it possible for the collection, analysis and correlation of technical data from the incident to be structured. The information is centralised, time-stamped and organised in such a way as to document the event accurately, establish responsibilities and support decision-making. The result is simplified survey work and considerable time saved for the teams.
- Continuous improvement in your level of security: thanks to forensic analysis, the response to every incident is a source of learning. By accurately identifying the attack vectors, exploited vulnerabilities and malicious behaviour targeting your business, you can adjust detection rules, strengthen existing controls and address vulnerabilities in a targeted way. DFIR is therefore perfectly in line with a continuous improvement approach to your cybersecurity.
- Ensuring compliance with current regulations: certain legislative frameworks, such as the NIS2 Directive, require companies to take measures to respond to incidents and notify the relevant authorities. The DFIR approach helps your company to meet these regulatory obligations.
- A lever for raising awareness among internal stakeholders: because they make the causes and concrete consequences of incidents visible, DFIR analyses are an excellent way of raising awareness among business units, HR departments and teams in the field, enabling them to adopt the right reflexes. This fosters a proactive security culture.
- Assistance in dialogue with cyber insurers: rapid access to reliable technical data (chronology, scope affected, type of attack) makes it easier to report incidents to cyber insurers. This can speed up the handling of the claim, avoid disputes and strengthen your position when negotiating future policies.
A DFIR SERVICE THAT CAN BE ACTIVATED 24/7
Thales Cybersecurity offers companies a DFIR service that can be activated 24/7,designed to take action rapidly in the event of a confirmed threat. As soon as the service is activated, we ensure global coordination from our SOCs based in 13 countries, and immediately mobilise our experts and tools to analyse the incident, contain the attack and eradicate the threat.
This response capability is based on a proven combination of forensic skills, automated collection and analysis tools, and in-depth knowledge of adversary tactics. The team responds quickly and effectively to critical questions: which systems have been compromised? What data were targeted? How was the intrusion carried out?
Our DFIR teams are capable of dealing with a broad spectrum of attacks: ransomware, compromised accounts, data exfiltration, advanced intrusions, etc. This expertise does not stop at resolving the incident: it is part of a sustainable resilience approach drawing on post-incident recommendations, simulation exercises and advice to strengthen your security in the long term.
Are you facing an emergency situation? Activate the DFIR service now to neutralise the threat and secure your systems.
