Spear Fishing: what is it and how can you avoid it?

On a day like any other, Juliette, HR manager at a small tech company, receives an email from the CEO urgently requesting the pay slips of two employees. The address seems legitimate, the tone familiar. She sends the files without a second thought. Except... it wasn't the CEO. It was a hacker who had taken the time to study the company's structure and roles, and who had imitated the internal codes perfectly. This is what's known as a spear phishing attack.

This type of targeted cyberattack is one of the most feared threats facing businesses today. Why is this? Because it exploits the most vulnerable link in the system: the human being. This article summarizes everything you need to know about spearfishing to avoid it as much as possible.

Understanding targeted phishing: definition of spear phishing

Spear phishing is an advanced form of phishing in which the perpetrator(s) target a specific person or group within an organization.

Unlike traditional phishing, which involves sending mass e-mails in the hope that a victim will take the bait, spear phishing is personalized and carefully prepared.

The attacker gathers information about his target (via LinkedIn, social networks, the company website or previous data leaks) to make his message credible. He then poses as a colleague, superior, partner or supplier. His objective: to retrieve sensitive data, gain access to a system, or obtain a fraudulent transfer.

A successful spear phishing attack can cost a company hundreds of thousands of euros, if not more. These attacks no longer only target large organizations. SMEs are increasingly affected, as they are often less well prepared to deal with them.

Spear phishing techniques

Spear phishing is essentially based onsocial engineering. In other words, the art of manipulating people into divulging confidential information or performing compromising actions. Here are the most widespread methods:

1. Email address spoofing

The attacker modifies the name displayed or uses a domain very similar to the company's (e.g. contact@rzilient.com → contact@rzilient.co). On mobile, only the name is visible, making the deception even more credible.

2. The false sense of urgency

Emails often contain a sense of urgency: "I need you to deal with this right away", "I'm in a meeting, can you take care of this now? The aim is to short-circuit the critical mind.

3. Mobile" signatures

The attacker signs off with "Sent from my iPhone" or "written on the move" to justify mistakes or an unusual email.

4. Malicious attachment or link

Sometimes, the aim is to install spyware. The e-mail then encourages the user to click on a link or open an attachment to infiltrate the information system.

5. The well-crafted pretext

We also talk about pretexting: a false, credible story that prompts the target to cooperate. This could be a fictitious recruitment, a call for tenders, or a security audit supposedly initiated by the CIO.

Some concrete examples of spear phishing

The fake CEO and gift cards

A classic. An accountant receives an email from the CEO urging him to buy 10 Amazon gift cards to "motivate the team". He pays for them, sends the codes and later discovers that the message was a fake.

The fictitious supplier

A purchasing department receives an RIB change request from a "regular supplier". The e-mail is well forged, and the invoice looks legitimate. Result: several tens of thousands of euros go to the wrong account.

Targeted HR

An email supposedly sent by the CFO requests the pay slips of several employees "for updating files". The Excel file is sent... and so is the sensitive data.

Best practices in spear phishing prevention

We'll never be able to totally prevent spear fishing attempts. But you can greatly reduce the risks by implementing the right reflexes and tools within your organization.

1. Raising employee awareness

Training teams to recognize the signs of an attack is the first line of defence. Regular workshops, cybersecurity quizzes and attack simulations are all effective ways of doing this.

2. Set up a secure messaging system

Use advanced security tools: sender filtering, domain verification, detection of suspicious attachments, etc. Some solutions even useAI to detect unusual behavior.

3. Systematically check sensitive requests

No request for transfers, personal data or password changes should be validated without a double check: a call, an internal message or hierarchical validation.

4. Limit data exposure

The less sensitive information your employees share online, the smaller the attack surface. Encourage sober professional profiles on LinkedIn and limit unnecessary public mentions.

5. Rely on a reliable IT platform

At rzilient, we offer an all-in-one platform that centralizes user management, automates access and facilitates the supervision of unusual activities. Thanks to our intelligent IT agent, abnormal behavior can be reported automatically, in conjunction with your HR and finance tools.

What's the difference between spear phishing and phishing?

Spear phishing and phishing are two terms often confused, but in reality they refer to very different approaches to phishing attacks. The main distinction lies in the level of personalization and the intended target.

Classic phishing is based on a mass strategy. Attackers send the same generic message to thousands or even millions of email addresses, hoping that a small percentage of victims will fall for the trap. The message may pretend to be from a bank, a utility or a well-known platform (such as Netflix or PayPal), and aims to trick the user into clicking on a malicious link or entering their credentials on a fake site.

In contrast, spear phishing is based on a surgical approach. The attacker identifies a specific person within a company (often an employee with access to sensitive data or critical functions) and develops a personalized message to gain that person's trust. The email is carefully crafted, with details of the victim's role, contacts, habits or current projects. Everything is designed to make the request appear legitimate.

In short, phishing is an attempt to trap everyone with a single lure. Spear phishing, on the other hand, targets a specific individual with a tailor-made lure. It's this sophistication that makes it harder to detect. And often far more costly if successful.

Differences and similarities between whaling and spear phishing?

In a way, whaling is a sub-category of spear phishing. But here, the target is even more specific: the company's top executives (CEO, CFO, COO, etc.). The hackers' level of preparation is therefore often more advanced. The potential damage is major (signature forgery, strategic leakage, large transfers, etc.).

Conclusion

Spearfishing is a very real, subtle and increasingly frequent threat. It's not a problem of antivirus or firewall, it's a problem of human vigilance, process and digital culture.

At _rzilient, we help companies build more secure, simpler and more automated IT. Thanks to our all-in-one platform, your accesses are better controlled, your teams better supported, and your data better protected.

‍Need toassess your risks or strengthen your security against spear phishing? Our experts will be happy to give you a demonstration of our tool.

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