Spear fishing: what is it and how to avoid it?

One day like any other, Juliette, HR in a tech SME, receives an email from the CEO urgently asking for pay slips for two employees. The address seems legitimate, the tone is familiar. She transmits files without thinking. Except... he wasn't the CEO. It was a Hacker who had taken the time to study the structure of the company, the roles of each person, and who had perfectly imitated the internal codes. This is what we call an attack of Spear Fishing (or spear phishing).

This type of targeted cyber attack is now among the threats most feared by businesses. Why? Because it exploits the most vulnerable link in the system: the human. This article summarizes you Everything you need to know about spear fishing to avoid it as much as possible.

Understanding Targeted Phishing: Definition of Spear Phishing

Spear phishing, or targeted phishing, refers to an advanced form of phishing in which the perpetrator (s) attack a specific person or group within an organization.

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

The attacker collects information about his target in advance (via LinkedIn, social networks, the company's website, or even previous data leaks) to make his message credible. He then impersonates a colleague, a supervisor, a partner or a supplier. Its objective: recover sensitive data, access a system, or obtain a fraudulent transfer.

Successful spear phishing can cost hundreds of thousands of euros to a business, or even more. These attacks no longer only target large organizations. SMEs are increasingly affected, as they are often less well prepared to deal with them.

Techniques used in spear phishing

Spear phishing is essentially based onsocial engineering. That is, the art of manipulating people to encourage them to disclose confidential information or perform compromising actions. Here are the most common methods:

1. Email address impersonation

The attacker changes the displayed name or uses a domain that is very similar to that of the company (e.g. contact@rzilient.com → contact@rzilient.co). On mobile, only the name is visible, which makes the deception even more believable.

2. The false sense of urgency

Email often contains a sense of urgency: “Need you to deal with this right away”, “I'm in a meeting, can you take care of it now? ”, etc. The objective is to Short-circuit critical thinking.

3. “Mobile” signatures

The attacker signs with a “Sent from my iPhone” or “written on the go” to justify mistakes or an unusual email.

4. The malicious attachment or link

Sometimes the goal is to install spy software. The email then encourages click on a link or open an attachment to infiltrate the information system.

5. The well-crafted pretext

We also talk about Pretexting : a credible false story that encourages the target to cooperate. This could be a fictional recruitment, a tender, or a security check allegedly initiated by the CIO.

Some concrete examples of spear phishing

The fake CEO and gift cards

A great classic. An accountant receives an email from the CEO asking to urgently buy 10 Amazon gift cards to “motivate the team”. He pays for them, sends the codes and later discovers that the message was fake.

The fictional supplier

A purchasing department receives a request for a change of RIB from a “usual supplier”. The email is well imitated, the invoice seems legitimate. Result: several tens of thousands of euros end up on the wrong account.

Targeted HR

An email allegedly sent by the DAF asks for the pay slips of several employees “to update the files”. The Excel file is sent... and so is the sensitive data.

Spear Phishing Prevention Best Practices

Spear fishing attempts can never be completely prevented. But we can greatly reduce risks by implementing the right reflexes and tools in the organization.

1. Raise awareness among employees

Train teams to Recognize the signs of an attack is the first line of defence. Regular workshops, cybersecurity quizzes, or even attack simulations are effective practices.

2. Set up a secure messaging system

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

3. Systematically check sensitive requests

No request for bank transfer, personal data or password change should be validated without double checking : a call, an internal message or a hierarchical validation.

4. Limiting data exposure

The less sensitive information your employees share online, the more you reduce the attack surface. Encourage simple 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 makes it easy to oversee unusual activities. Thanks to our intelligent IT agent, abnormal behaviors can be reported automatically, in connection with your HR and finance tools.

What's the difference between spear phishing and phishing?

Spear phishing and phishing are two terms that are often confused, but they actually refer to very different approaches to phishing cyberattacks. The main distinction is due to the level of personalization And at the Aimed target.

Classic phishing is based on Mass strategy. Attackers send the same generic message to thousands or even millions of email addresses, hoping that a small percentage of victims fall into the trap. The message can be impersonated by a bank, a public service or a well-known platform (such as Netflix or PayPal), and aims to push the user to click on a malicious link or to enter their credentials on a fake site.

Conversely, spear phishing is based on 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 their trust. The email is carefully written, with details about the victim's role, contacts, habits, or ongoing projects. Everything is designed to make the request appear legitimate.

In summary, phishing attempts to trick everyone with a single bait. Spear phishing, on the other hand, is aimed at a specific person, with a tailor-made lure. It is this sophistication that makes it more difficult to detect. And often much more expensive if successful.

What are the differences and similarities between whaling and spear phishing?

The Whaling is in a sense a sub-category of spear phishing. But here, the target is even more specific: these are the senior company executives (CEO, CFO, COO, etc.) The level of preparation of hackers is therefore often more advanced. The potential damages are major (signature usurpation, strategic leak, large transfers, etc.).

Conclusion

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

At _rzilient, we help businesses build a Safer, 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.

‍Do you need to assess your risks or strengthen your security against spear phishing? Our experts are at your disposal to offer you a demonstration of our tool.

‍

‍