How does recon work in cybercrime and how can we defend against it?
Before a cyber attack, hackers often spend weeks gathering information about their target. This hidden, preparatory phase is called reconnaissance. In this article we explain how this process takes place and how to protect against it.
What is recon?
Reconnaissance is the first, preparatory step in cyber attacks. The attacker does not make direct contact with the target, but simply gathers information about the target - for example, a company's network, website or systems.
The aim is to map the systems in place, the software in use and identify potential weaknesses. This monitoring is often done completely unnoticed, by analysing public sources, social media or technical impressions.
A recon is like a burglar first looking around the house: assessing the defences, the entry points and only then deciding on the actual action.
Types of recon
There are basically two types of recon:
Passive recon
The attacker does not make direct contact with the target system, but merely observes. It analyses public databases, social networking sites, network traffic to gather information undetected. Although it remains invisible, this data can provide an accurate picture of the target - making it particularly dangerous.
Active recon
In this case, the attacker is already directly scanning the system - for example, by port scanning or searching for vulnerabilities. This can lead to more detailed technical data, but the activity can leave traces in the logs, increasing the risk of detection.
The steps of recon in preparing a cyberattack
During the recon, the attacker builds the plan of attack step by step.
1. Gathering information
It uses public sources - company websites, social media, press releases - to collect basic information about the target: systems used, IP addresses, domain names, available email addresses.
2. Mapping the network
It then defines the structure of the target network: IP ranges, devices, subnets. It often uses IP or port scanning to find potential ingresses.
3. Identification of protection systems
The attacker will try to detect active security solutions such as firewalls, IDS systems or endpoint protection to avoid detection.
4. Mapping open ports and running services
Attackers use automated tools to look for "open doors" to the network: open ports, misconfigured or forgotten services. They then analyse what software is running at these points, and if, for example, an old version of a web server with known vulnerabilities is running, it could be a perfect target.
5. Create a network map
The final step is for the attacker to visually map the entire system: where the key points, databases, routers are located and the routes to reach them - preferably from the direction of least resistance.
How can we defend against recon (reconnaissance) attacks?
Prevention and constant vigilance are the keys to protecting against recon attacks. The following security methods can help you identify and block recon attempts before they cause serious damage.
1. Network monitoring
One of the most effective forms of protection is active monitoring of the network. This means that the organisation constantly monitors and analyses network traffic in order to detect suspicious activity.
Examples of such activities include port scanning or network mapping - these are often signs that an attack is imminent. Early detection gives us the opportunity to intervene in time.
2. Honeypots
A honeypot is a deliberately vulnerable-looking decoy that distracts attackers from real systems while gathering valuable information about them.
These lures will help:
- to divert attention from critical systems,
- observe the behaviour of the attacker,
- and gather information on the techniques used, without any risk.
A well-designed honeypot not only warns of recon activity, but also actively helps to develop a defence strategy.
3. Firewalls and access control
Firewalls play an essential role in controlling incoming and outgoing network traffic - they are the first "gatekeepers".
And access control systems ensure that only authorised users have access to sensitive areas within the network. These can significantly reduce the chances of a successful recon attack, as less information can leak out of the system.
4. Regular updates and patch management
Attackers often look for software flaws or old versions that contain known vulnerabilities. Keeping systems and applications up to date is therefore essential.
Effective patch management includes:
- constantly checking for updates,
- install them quickly but safely,
- and post-application monitoring.
This not only eliminates weaknesses that can be exploited in recon attacks, but also strengthens the cybersecurity resilience of the organisation in general.
5. Data encryption and data protection measures
Encryption is the process of converting data into a format that can only be decrypted with the right key. This way, if an attacker were to gain access to the data, they would not be able to interpret it.
Important:
- the data at rest and
- data in transit must be encrypted.
In addition, data masking, access restriction and other data protection techniques further narrow the attackers' scope.
6. Threat intelligence
Threat intelligence helps you to anticipate the types of attacks you can expect. This information:
- from hacker forums,
- from dark web monitoring,
- or from automated monitoring systems.
Based on the data collected, the organisation can implement targeted protection measures before an attack occurs.
7. Staff training and awareness-raising
In addition to technological protection, the human factor also plays a key role. Behind most successful attacks is some kind of human error - a hasty click or a weak password, for example.
During security awareness training, staff will learn:
- how to recognise suspicious signs,
- how to protect their own access,
- and what to do if an attack is suspected.
A prepared, alert team is also the best first line of defence against recon attacks.
Reconnaissance attack: frequently asked questions
Finally, here are some frequently asked questions about recon attacks!
What do recon attacks look like in practice?
In a recon attack, the attacker gathers information about the target in preparation for the real attack. This can be:
- port scanning to map open services,
- search for employee details on social media,
- sending phishing emails for testing purposes,
- network architecture and software version identification,
- collecting public company information from websites.
All of this is seemingly harmless, but it plays a critical role in the preparation of targeted attacks.
Why is reconnaissance important in cybersecurity?
Understanding how this phase works can help you spot early warning signs - such as port scanning or suspicious data collection.
Early detection of detection attempts allows us to act before attackers can cause real damage. It also helps us to see what information is publicly available about us, and to reduce it to narrow our attack surface and strengthen our defences.
Is reconnaissance the same as espionage?
Not entirely. Reconnaissance is about gathering technical information - about systems, networks, security solutions - in preparation for a cyber attack.
Espionage is a broader concept and can involve obtaining any kind of secret or sensitive data, even for political or economic purposes.
Both are done in secret, and hackers often use espionage-like methods to recon.
How do I know I've been cyber-attacked?
There are several telltale signs of a cyber attack, such as:
- unusual network traffic,
- slow system or unexpected errors,
- unknown user accounts,
- unsuccessful logins,
- anti-virus warnings,
- suspicious emails or communications,
- the appearance of unlicensed software.
Most importantly, check your log files regularly and investigate any odd discrepancies immediately - so you can detect and stop an attack in time.
Prevent cyber attacks! Contact us and let's build a safer, more resilient digital environment together - with expertise, experience and reliable solutions!
