Amsterdam, May 12, 2025 - Two Dutch cybersecurity companies – Hadrian and Passguard – are joining forces to secure businesses against the new wave of cyber attacks. “Hackers are constantly changing their methods, we need to see what criminals see and know what they know. This way, we take action before the attack is launched”, says Rogier Fischer, CEO of Hadrian

An infostealer infection means that your data is in the hands of cybercriminals. If you've been notified of an infostealer infection on your device, it’s important to act quickly. This way, you can prevent further damage. In this guide, you’ll read what an infostealer infection means and the three steps you need to take to limit the consequences.

Recently, Tom Leijte spoke with Security Innovation Stories, a platform that gathers innovative stories from the cybersecurity sector. In this interview, Tom not only shared insights into the world of infostealers but also revealed the story behind the founding and mission of Passguard.

Following the news about the tens of thousands of Dutch victims of infostealers, RTL News tech reporter Daniël Verlaan was invited to the desk at RTL Z. During the interview, Verlaan shared insights into the research and operation of infostealers.

After the media exposure about infostealers at RTL News and AD, we received a lot of questions. A frequently asked question, including on Reddit, was: “Why do you specifically recommend Sophos to combat infostealers?” A fair question, and in this blog post, we would like to take you into account our considerations.

Following the report on RTL Nieuws, Algemeen Dagblad reached out to Passguard for an interview with our founders, Tom and Sanno, about the dangers of infostealers.

Infostealers are causing thousands of victims, including in the Netherlands. Research that we carried out together with RTL News shows that more than 40,000 Dutch people have already been infected with this dangerous malware. As a result, passwords, private data and business data are out on the street.

Infostealers are on the rise, and with them, the statistics tracking this growing threat. Many companies publish reports, but what do those numbers really mean? We delved deeper into the data to give you the full story. No time to go through it all? Our Passguard rating system scores the value of statistics on a scale from 1 to 5. Convenient, right?

Infostealers are on the rise, and with them, the statistics tracking this growing threat. Many companies publish reports, but what do those numbers really mean? We delved deeper into the data to give you the full story. No time to go through it all? Our Passguard rating system scores the value of statistics on a scale from 1 to 5. Convenient, right?

Infostealers are on the rise, and with them, the statistics tracking this growing threat. Many companies publish reports, but what do those numbers really mean? We delved deeper into the data to give you the full story. No time to go through it all? Our Passguard rating system scores the value of statistics on a scale from 1 to 5. Convenient, right?

Infostealers are on the rise, and with them, the statistics tracking this growing threat. Many companies publish reports, but what do those numbers really mean? We delved deeper into the data to give you the full story. No time to go through it all? Our Passguard rating system scores the value of statistics on a scale from 1 to 5. Convenient, right?

Infostealers are on the rise, and with them, the statistics tracking this growing threat. Many companies publish reports, but what do those numbers really mean? We delved deeper into the data to give you the full story. No time to go through it all? Our Passguard rating system scores the value of statistics on a scale from 1 to 5. Convenient, right?

Infostealers are on the rise, and with them, the statistics tracking this growing threat. Many companies publish reports, but what do those numbers really mean? We delved deeper into the data to give you the full story. No time to go through it all? Our Passguard rating system scores the value of statistics on a scale from 1 to 5. Convenient, right?

Infostealers are on the rise, and with them, the statistics tracking this growing threat. Many companies publish reports, but what do those numbers really tell us? We dug deeper into the data to give you the full picture. No time to go through everything? Our Passguard rating system scores the value of these statistics on a scale from 1 to 5. Convenient, isn’t it?

The Graafschap College, a medium-sized vocational school in Doetinchem, has around ten thousand students and over a thousand employees. Rob Gerritsen, Chief Information Security Officer (CISO) at Graafschap College, gained insight into his organization's dark web exposure through Passguard. During a walk through a wintery forest near Doetinchem, he spoke to us about his experiences.

Our colleague Tom Leijte spoke to Topicus KeyHub about the rise of and the risks they pose to organizations. From stolen session cookies to digital identity misuse—it's a growing problem that needs action.

Information security is gaining increasing attention in healthcare organizations. We spoke about this with a large healthcare organization in the south of the Netherlands. Information security is an important theme for them: they continuously map out vulnerabilities and implement improvements. One of the tools they use for this is Passguard. Why? We asked the CIO.

Bijna dertig inschrijvingen, slechts tien deelnemers: op 3 oktober nam Passguard, samen met negen andere startups, deel aan de Cyber Investor Days in Den Haag, georganiseerd door de European Cyber Security Organisation (ECSO), met samenwerking van Women4Cyber, TIN Capital, InnovationQuarter, KPN Ventures, Security Delta (HSD) en de stad Den Haag.

Het is één ding om van een leverancier te horen hoe goed hun oplossing werkt, maar het is veel krachtiger om van een klant te horen hoe die oplossing in de praktijk wordt toegepast.

With over 8,500 homes in around 11 municipalities and 100 employees, Omnia Wonen is a medium-sized housing corporation. You might wonder if organizations of this size can also benefit from dark web intelligence. Gerben Naaktgeboren, advisor for Information and Automation at Omnia Wonen, shares his insights.

More than 50 information security professionals from public libraries across the Netherlands gathered today in the beautiful theater hall of the Utrecht Library, located in the historic building on the Neude. The purpose? To discuss the latest insights in information security. Among the speakers were Aleid Wolfsen, Chairman of the Dutch Data Protection Authority, and our own Tom Leijte, CEO and Co-Founder of Passguard.

Government agencies rarely give explicit attention to the growing threat of infostealers, but Down Under, that's changing. The Australian Cyber Security Centre (ACSC) recently released their report The Silent Heist, a deep dive into the infostealer ecosystem. Here are the five most important findings.

With 12,500 employees worldwide, dozens of shipyards, and a turnover of several billion euros, Damen Shipyards is the largest shipbuilder in the Netherlands. In addition to civilian vessels, Damen is also active in the construction of military ships for navies and coast guards. To map out dark web data and infostealer infections, it uses Passguard. Hans Quivooij, CISO of Damen Shipyards, explains why.

Royal FloraHolland, the leading international marketplace for floriculture, is also a frontrunner in cyber security. As a co-initiator of the Greenport Cyber Resilience Center, they provide growers and buyers with essential protection against digital threats through their RFH Cyber Subscription. To address the challenge of infostealers, Royal FloraHolland uses Passguard. Why? We spoke to Bas Wevers, Chief Information Security Officer (CISO) at Royal FloraHolland.

How does an attack on an organization using an infostealer unfold? Examining examples such as Uber and EA Games reveals a four-step plan utilized by attackers to target an organization.

Preventing infostealer infections can be broken down into two key steps. While the first step is usually relatively straightforward, the second is often much more challenging.

If you suspect that your organization is dealing with an infostealer infection, it’s crucial to act quickly and decisively. Follow these steps to get the situation under control and prevent further damage.

It may sound a bit crude, but we often compare infostealers to dog poop: they don’t come flying at you, but you simply step into them. In other words, infostealer infections are almost always the result of user behavior. At this stage, infostealer attacks are generally not yet targeted at specific organizations or users.

Managing the infostealer risk is challenging not only because of the versatility and stealthy nature of this malware but also due to where the risk primarily occurs: on unmanaged devices that have access to internal environments, such as employees’ personal laptops or suppliers’ computers.

If an employee's device is infected with an infostealer – even if it’s not a managed device – the attacker has the same access to internal systems and data as the employee does through that device. This access poses a significant risk for organizations and can result in data breaches and hacks.

An infostealer is a specific type of malware designed to steal as much valuable information from devices as possible. This includes locally stored files and login credentials. Session tokens, stored in cookies, are especially valuable to infostealers. Such data can be exploited to gain access to active sessions, even when multi-factor authentication (MFA) is enabled.

Infostealers are developed as Malware-as-a-Service (MaaS). This model allows cybercriminals without deep technical knowledge to gain access to advanced malware by simply paying for a subscription. This makes infostealers more accessible for a wider range of criminals to launch attacks without having to develop malware themselves.

In recent years, many organizations have implemented effective measures to secure their networks and reduce the risk of phishing attacks. As a result, the effectiveness of traditional attack methods has significantly decreased. This poses a major problem for cybercriminals, as their entire ecosystem relies on successful attacks.