Infostealers: what they are and how to defend yourself  

An infostealer is a malicious software designed to extract the victim’s personal information, including credentials, banking data, and any other valuable information.   

This type of attack is increasingly used and requires a proper prevention strategy by companies and institutions. 

Infostealer attacks are increasingly prevalent

In an increasingly complex IT landscape from a cybersecurity perspective, malicious software called “infostealer” is one of the most widely used attack techniques.

The infostealer acts by infecting victims’ systems and stealing their data, such as banking data and credentials.

According to Cert-Agid‘s report, 78% of malware spread in Italy in 2023 belongs to the infostealer category.

This is an emblematic figure that underscores the importance of constantly updating our defense strategies so as not to be unprepared against emerging threats.

The characteristics of infostealers

As mentioned, an infostealer is a malicious software (malware) that seeks to steal information of all kinds.

More complex malware such as banking Trojans (e.g., TrickBot) and stalkerware usually include infostealer components. In most cases, this means stealing information that can bring money to cybercriminals.

Infostealers silently infiltrate systems and focus on specific targets, such as:

• Login credentials (usernames and passwords for email, social media and corporate accounts)

• Banking data (credit cards, cryptocurrency wallets)

• Sensitive information (documents, screenshots or activity logs)

• Authentication tokens to bypass two-factor security systems

These malware often act invisibly, recording every user interaction with the infected system, from a simple click to sending personal information

How infostealers spread

An infostealer spreads through common communication channels via phishing, one of the most common types of hacker attacks.

These include business tools such as email attachments, malicious links, and malicious softwares, items commonly used by staff within a company.

These tools are excellent entry points for infostealers, who can break into a system through various types of malicious programs, for example by hiding inside applications that, at first glance, has a completely legitimate operation, like spyware.

This feature misleads users of a company who, unbeknownst to them, click on links and attachments that are considered trustworthy, or enter their credentials within apps that mimic in every way an original software, for example, for internet banking or online payments.

How to defend yourself

Countering infostealers requires a combination of advanced technology and awareness. Below we look at some examples:

• Endpoint protection – EDR and XDR solutions can detect abnormal activity related to infostealers 

• Strong authentication – Implementing multi-factor Authentication (MFA) systems reduces the effectiveness of credential theft

• User education – Raising awareness against phishing remains a key defense  

• Continuous monitoring – Monitoring systems for compromise is crucial

As with many other cyber threats, training users is the most immediate way to prevent information theft.

Phishing is the most common technique used to spread an infostealer, so training staff to recognize bogus links, malicious attachments and fake applications with real simulated phishing attacks is important.

In a company that constantly handles large volumes of emails, links of various types, and customer and vendor banking data, training staff to know the possible entry points for an infostealer can dramatically reduce the risk of incidents.

To avert these risks, it is therefore crucial for companies, organizations, and private citizens to have effective and proper security awareness, to be as aware as possible of the cyber risks to which they are exposed.  

Learn about Telsy’s cybersecurity solutions or contact us at contact@telsy.it to learn more.