Definition
In Cybersecurity, reconnaissance is the initial stage of a cyberattack, where an attacker gathers information about a target system, network, or organization to identify vulnerabilities and execute an attack.
This data may include security measures, the system’s architecture, the software version, and information about the system or network users.
How Reconnaissance Works
- First, the attacker identifies a target ( a specific system, network, or organization).
- The attacker begins to gather information about the target. This may involve searching online resources, scanning open ports, and analyzing network traffic.
- This information helps the attacker to detect security vulnerabilities and plan the attack.
- The attacker initiates the attack to access the target’s system or steal sensitive information.
Common Reconnaissance Techniques
- Network mapping: The attacker constructs a map of the target network (e.g., the network topology, IP addresses, and connected devices). You can prevent network mapping by adopting tools that identify and block scans of your network or systems.
- DNS enumeration: An attacker can collect information about the target’s domain name system (DNS) to detect email servers, subdomains, and other information they can use in the attack. Organizations can adopt DNS security measures (like encryption and rate-limiting) to prevent DNS enumeration.
- Port scanning: The attacker looks for open ports to access a network. You can configure firewalls to block inbound traffic on unused ports while allowing traffic only on ports essential for your business operation.
- Social engineering: Attackers can manipulate people to provide sensitive information they can use in an attack. Organizations can prevent social engineering by educating their employees on identifying and responding to phishing attacks.
- OS fingerprinting: An attacker can examine network traffic to identify the target’s operating system, which they can use to detect potential vulnerabilities. Organizations can prevent OS fingerprinting by using tools that obscure their OS information or provide false responses when a fingerprinting attempt is made.