What is Exfiltration?

Exfiltration is the unauthorized transfer of data from a computer or network by an attacker or other entity. In a cybercrime scenario, exfiltration is typically the final stage of a cyberattackWhat is a Cyberattack? A cyberattack is a deliberate and malicious attempt to exploit vulnerabilities in computer systems, networks, or software applications to cause damage, steal information, disrupt services, or… More, taking place after an attacker has gained access to an organization’s systems and gathered data. Exfiltration culminates in an attacker moving data out of a compromised environment to a location under their control.

Exfiltration Stages

Cybercriminals typically execute exfiltration in four stages:

1. Initial Compromise: The attacker gains access to the target’s systems through one of several techniques, including phishingWhat is Phishing? Phishing is a type of cyberattack in which attackers send fraudulent communications, or direct people to counterfeit websites in order to trick those individuals into revealing sensitive… More, qishingWhat is Qishing?Qishing, also known as quishing, is a form of phishing that uses QR (Quick Response) codes to deceive the victim. Rather than launching a phishing attack with a… More, or business email compromise.
2. Privilege Escalation and Lateral Movement: The attacker escalates account privileges to gain higher-level access and move laterally across the network, allowing them to discover and compromise further systems and resources.
3. Data Discovery and Collection: The attacker searches for valuable data in databases, file servers, cloud environments, or other areas of the network, collects it, and prepares it for exfiltration.
4. Exfiltration: The attacker transfers the collected data from the target environment to an external location, such as a remote server, cloud environment, or physical storage device.

Exfiltration Methods

There are four key exfiltration methods you should be aware of. They are:

1. Network-Based Exfiltration: This includes via HTTP/HTTPS, FTP/SFTP, email, or DNSWhat is DNS? The Domain Name System (DNS) is a critical component of the internet, functioning like a phone book for the digital world. It translates user-friendly domain names, such… More tunneling.
2. Cloud-Based Exfiltration: Attackers upload stolen data to cloud storage services like Google Drive, Dropbox, or Amazon S3, often via misconfigured or exploited APIs.
3. Physical Exfiltration: Attackers may steal a physical device, such as a USB drive, laptop, or mobile phone.
4. Steganography: More sophisticated attackers may hide data in other files, such as images, videos, or audio files, to exfiltrate undetected.

Impacts of Exfiltration

Victims of exfiltration can face financial and legal consequences. Attackers may use exfiltrated data to plan further attacks, disrupt operations, hold an organization to ransom, or steal money directly. Customers may decide to switch providers in the wake of an incident. Organizations that have not demonstrated adequate security can face regulatory fines, such as those associated with GDPRWhat is GDPR? The General Data Protection Regulation (GDPR) is widely regarded as the world’s strictest security and privacy law, promulgated by the European Union (EU) to regulate any organization… More and HIPAAWhat is HIPAA? The Health Insurance Portability and Accountability Act (HIPAA) is a comprehensive piece of legislation enacted by the United States Congress in 1996.It serves as a vital safeguard… More.

Combatting Exfiltration

To combat exfiltration, organizations should implement a multi-layered, cohesive cyber security strategyWhat is a Security Strategy? A security strategy is a comprehensive plan that outlines how an organization will protect its digital and physical assets from threats and vulnerabilities. It encompasses… More that includes at least the following tools and concepts:

• Network Monitoring and Anomaly Detection: Such as Intrusion Detection Systems (IDS), Intrusion Prevention Systems (IPS), and Security Information and Event Management (SIEM) platforms.
• Data Loss Prevention (DLP)Data Loss Prevention (DLP) is a comprehensive approach and set of technologies designed to prevent the unauthorized disclosure or leakage of sensitive and confidential information from an organization. More: These tools are used to classify sensitive data, such as intellectual property or personal information, and enforce policies that prevent unauthorized access or movement of this data.
• Strong Access Controls: Access controls based on the principle of least privilege ensure users have only the minimum access necessary to perform their functions.
• EncryptionWhat is Encryption? Encryption converts readable data (plaintext) into a scrambled and unreadable format (ciphertext) using an algorithm and a key. The primary purpose of encryption is to ensure the… More: Strong encryption methods render data useless to attackers, making them less likely to exfiltrate it.
• Endpoint Protection and Monitoring: Endpoint protection tools like antivirus, anti-malware, and Endpoint Detection and Response (EDR)What is EDR? Endpoint Detection and Response (EDR) is a cybersecurity solution that proactively identifies and responds to threats to devices on a network, including desktop PCs, laptop PCs, mobile devices… More can detect and block exfiltration attempts from compromised endpoints.
• Incident Response: Incident response plans should address exfiltration scenarios. The plans should be regularly updated.
• Employee Awareness Training: Educate employees on recognizing phishing attacks and suspicious behavior and handling data correctly.

The Future of Exfiltration

Increasingly sophisticated attack methods, including those driven by AIWhat is AI? Artificial Intelligence (AI) refers to the simulation of human intelligence processes by computers in an aim to mimic or exceed human cognitive abilities across a range of domains…. More, encrypted channels, and steganography, will define the future of exfiltration. Similarly, the rise of quantum computingWhat is Quantum Computing? Quantum computing is a cutting-edge field that leverages the principles of modern physics to perform operations significantly faster than classical computers. Classical computers, including the laptops,… More could challenge existing encryption methods and make data more vulnerable. Moreover, as organizations strengthen their defenses, attackers will likely target less secure endpoints, IoTWhat is the IoT? IoT, or Internet of Things, refers to the network of interconnected devices embedded with sensors, software, and other technologies, enabling them to collect and exchange data… More devices, and cloud environments to exfiltrate data.

Security measures will need to advance to combat these evolving threats. They should focus on real-time detection, AI-driven anomaly detection, and adaptive encryption techniques, ensuring data protectionWhat is Data Protection? Data protection refers to the practice of safeguarding sensitive information from unauthorized access, disclosure, alteration, or destruction. It involves implementing policies, procedures, and technologies to ensure… More in a rapidly changing technological landscape.

For more cybersecurity terms and definitions, visit our glossary pages here.