What is spear phishing?

If this is not your first visit to our blog, you probably already know what phishing is. If you don’t, be sure to check out this post. Basically, phishing is a type of fraud that aims to extract personal data: logins, passwords, wallet numbers, and so forth. It’s essentially digital social engineering.

There’s a variety of phishing known as spear phishing. What distinguishes spear phishing from other types of phishing is that it targets a specific person or employees of a specific company.

That targeting makes spear phishing more dangerous; cybercriminals meticulously gather information about the victim to make the “bait” more enticing. A well-produced spear phishing e-mail can be very difficult to distinguish from a legitimate one. So, spear phishing makes it easier to hook the victim.

Two motives lie behind spear phishing: stealing money and/or getting secrets. In either case, the first task is to penetrate the corporate network. The usual approach is sending employees e-mails with malicious documents or archives attached. For example, that’s how the group behind the Silence attacks operated.

A document can be weaponized by using macros in Microsoft Word or JavaScript code — basically tiny, no-frills programs built into standard files with the sole purpose of downloading far more serious malware onto a victim’s computer. This malware then spreads over the target network or just intercepts all the information it can get hold of, helping its creators to find what they’re looking for in the network.

Spear phishing is not for small-time scammers, who try to cast their net as wide as possible. Bog-standard fraudsters don’t have the time or means to customize their weapons.

Spear phishing is a tool for major attacks on large enterprises, banks, or influential people. It is deployed in large APT campaigns, like Carbanak or BlackEnergy. Spear phishing was also used in the Bad Rabbit attacks, which began with an e-mail infection.

The most common targets of spear phishing are either high-level employees with access to potentially juicy info, or departmental staff whose work involves opening lots of documents from outside sources.

Take, for example, HR departments. They get many resumes in all kinds of formats. Receiving e-mails with attachments from unknown sources isn’t the least bit surprising or suspicious. PR and sales are also vulnerable, as are many other areas.

Accounting departments are in a special risk zone. To begin with, they deal with contractors, regulators, and heaven knows who else. And, of course, they work with money and banking software. For cash-hungry hackers, accounting is ripe for the picking.

Spies, meanwhile, are interested in people with inside access to systems — system administrators and IT staff.

But don’t be fooled into thinking that spear phishing is only aimed at large companies. SMBs are every bit as interesting to intruders. It’s just that whereas large enterprises are more likely to get spied on, SMBs are more likely to suffer from theft.

In general, the most effective techniques to guard against spear phishing are roughly the same as for the other types of phishing. See our post with 10 tips for maximum protection against this threat. The only difference is that spear fishing demands an even more eagle-eyed approach.

Ideally, phishing e-mails should not reach your mailbox at all. In a business infrastructure, such messages should be filtered out at the corporate mail server level. Special software packages can assist. For example, Kaspersky Security for Mail Server uses cloud technologies to block malicious attachments and phishing links.

However, for better results, the security system should be multilayered. After all, it’s possible in theory (and practice) for employees to use third-party mail services or receive a phishing link in an instant messenger. Therefore, it’s better to equip workstations with a solution capable of detecting malicious activity in applications that attackers usually exploit. One such solution is Kaspersky Endpoint Security for Business.