Infostealers: The Malware That Breaks in Without Breaking Anything

In 2026, cybercriminals are slipping through the cracks of organizations to harvest and sell sensitive data. Infostealers, the stealthiest tool in a threat actor‘s arsenal, are the weapon of choice, moving into places they shouldn‘t be without alerting security systems.

IBM reported that 1 in 3 incidents observed in 2025 involved credential theft, where criminals were “breaking in without breaking anything.” The latest attacks make it more difficult for cybersecurity professionals to catch a potential data breach.

Even Mac users are vulnerable to the new era of infostealer malware. Microsoft has warned that cybercriminals are rapidly evolving, targeting both Windows and Mac to gather more stolen credentials than ever before.

In this guide, we‘ll walk you through the latest advancements in infostealer malware technology and what you can do to keep your organization protected.

What are infostealers?

Information stealers are a type of malware-as-a-service (MaaS) that collects sensitive information from a device.

Cybercriminals use information-stealing malware to take login credentials for resale on the dark web or for future cyberattacks, such as phishing campaigns and ransomware attacks.

Infostealers do more than just credential theft; they steal:

• Session cookies and tokens to hijack accounts.
• Browser data, including browser history, search history, autofill data, and saved credit card details.
• Crypto‑wallet data and crypto keys to steal funds.
• System information such as OS versions, installed apps, and IP addresses.
• Screenshots of sensitive data.
• Files including PDFs, documents, and email logs.

How do infostealers differ from other types of malware?

While there are many types of malware out there for threat actors to use, infostealers are one of the most popular for their stealthy nature and quick exfiltration.

Here‘s how infostealers differ from other types of malware:

• Trojans can give a hacker remote access and control, but they‘re more complex to operate.
• Ransomware can infect and extort victims, but they‘re not quiet and don‘t persist.
• Keyloggers and spyware can record and watch input data, but it‘s not great for exfiltration.

Infostealers come ready-to-go from the dark corners of the internet. Subscription plans and customer support for MaaS make this type of cybercrime accessible.

Once a device is infected, threat actors can collect the data they want in seconds and disappear without the infection being flagged by anti-virus software.

Infostealers in 2026

In 2026, infostealer malware infections are becoming more popular due to the low barrier to entry and easy-to-use interface. Their functionality enables even entry-level hackers to use stolen credentials for social engineering attacks or to gain extra funds by selling data sets on the dark web.

• The identity theft market in 2026 is booming, given the demand for data sets that can be used against employees and organizations.
• In late January 2026, a database with 149 million passwords was discovered, along with 48 million Gmail email accounts and 6.5 million Instagram accounts.
• Hackers aren‘t just after business logins; they‘re after information about employees, like their social media accounts, banking accounts, even streaming service accounts—any compromised online account that can give them greater access.

Threat actors commit identity theft to give them quick access to funds, like draining bank accounts and opening credit cards in the victim‘s name.

For businesses, just one exposed employee allows a hacker to bypass security protocols, gather company financial information, and make a profit by reselling this information on the dark web.

Comparison table of the major infostealer families (2025 – 2026)

Family	First Seen / Peak Era	Primary Capabilities	Typical Targets	Notes (2025–2026)
RedLine	~2020, still dominant	Browser creds, cookies, crypto wallets, system info	Individuals, SMBs, initial access for ransomware	Huge volume in stealer‑log markets; still one of the top families.
Raccoon v2	Re‑emerged 2023+	Credentials, cookies, autofill, crypto, system info	Broad consumer base, small orgs	Returned after law‑enforcement disruption; active MaaS in 2025.
Vidar	~2018, persistent	Credentials, cookies, crypto, system profiling, files	Gamers, piracy ecosystems, consumers	Frequently bundled with cracked software and malvertising.
Lumma (LummaC2)	2022+, surging	Credentials, cookies, crypto, 2FA data, system info	Corporate & personal accounts	Very rapid development; strong focus on session tokens.
RisePro	~2022	Credentials, cookies, crypto, system info	Global consumer base	Common in stealer‑log shops; often paired with loaders.
Rhadamanthys	2022+	Credentials, cookies, crypto, system info, files	Higher‑value corporate & financial targets	Advanced panel, strong obfuscation, active MaaS.
MetaStealer	2023+	Browser data, credentials, cookies	macOS users, creatives, small studios	Notable for macOS focus and fake‑job lures.
Stealc	2023+	Credentials, cookies, crypto, system info	Broad, often via malvertising	“All‑in‑one” stealer, frequently rotated in campaigns.

What are the most active infostealer families in 2026?

In the last 2 years, IBM noted that Lumma Stealer, RisePro, and RedLine Stealer were among the top 5 infostealers used by threat actors.

IBM dark web investigations revealed infostealer malvertising increased by 12% in 2024, making them a more prolific threat to businesses.

Here are some examples of how infostealers work.

1. RedLine Stealer

Available on the dark web as a Malware-as-a-Service (MaaS), RedLine Stealer grabs login credentials, autocomplete fields, passwords, and credit card information from browsers. It can also exfiltrate data on the user‘s OS, hardware configuration, location, and any installed security software.

Distribution: RedLine Stealer is often shared in malicious attachments sent via phishing emails. As a Trojan, RedLine is also embedded into malicious software that appears to be legitimate.

2. Raccoon Stealer

Raccoon Stealer v2 is an infostealer specializing in stealing sensitive data stored in users‘ browsers, specifically session cookies, saved login details, and credit card details.

For cryptocurrency wallets, Raccoon Stealer targets public keys, private keys, and seed phrases to compromise accounts.

Distribution: Raccoon Stealer is usually promoted through SEO-poisoned websites that offer “free” or cracked software.

3. Lumma Stealer

Lumma Stealer has continued to rise in popularity amongst cybercriminals. Lumma specializes in credential and token theft, allowing attackers to bypass multi-factor authentication (MFA) to hijack accounts. Even VPNs can be compromised by collecting the session tokens and configuration files.

Distribution: Lumma Stealer is usually distributed on the dark web and sold as a subscription. Using obfuscated PowerShell scripts, threat actors drop the malware into the victim‘s environment to steal data undetected.

4. Vidar Stealer

Vidar Stealer focuses on credential theft, stealing browser passwords, cookies, autofill data, crypto‑wallet information, and detailed system fingerprints.

Distribution: Methods to distribute Vidar have evolved from malicious email attachments and malvertising campaigns to a MaaS subscription model sold on the dark web. In some cases, Vidar has mimicked legitimate software updates, secretly embedding the malware.

5. RisePro Stealer

RisePro is a rising infostealer designed to grab credit cards, passwords, and crypto wallets from infected devices.

Distribution: RisePro is embedded in cracked versions of popular software sold online, game modifiers, and key generators. RisePro has links to PrivateLoader, a malware distribution service, which uses its network of fake and malicious websites to distribute the malware.

7-step infostealer infection chain

Infostealers compromise an organization from the inside, delivered under the guise of legitimate software, before exfiltrating and encrypting sensitive data straight to the threat actor‘s server.

To protect your organization from infostealer malware, it‘s imperative to understand the full infection chain.

1. Delivery

• Cybercriminals embed infostealer software into malicious files and attachments, tricking users into downloading and installing the malware onto their devices.
• Infostealers are hidden within phishing emails, malvertising campaigns, scam sites, fake browser updates, cracked software, fake installers, or a loader that drops the stealer.
• The goal is to make the infostealer malware appear legitimate to systems.

2. Execution

• Once the victim opens the malicious file, the infostealer malware performs anti-analysis checks to avoid sandboxes and virtual machines, then prepares modules for data theft.
• Infostealers operate within the memory of a device, completing their operation within seconds to avoid detection.

3. Reconaissance

• Before the infostealer starts taking sensitive data, the malware gathers information about the operating system (OS) to discern which data is available and valuable.
• Infostealers gather information on browser versions, OS details, system architecture, hardware details like CPU, GPU, and RAM specs, IP addresses, geolocation data, installed security tools, and system language.

4. Data harvesting

• At this stage, the infostealer can begin harvesting sensitive data.
• Data commonly stolen includes saved browser credentials, FTP accounts, session cookies and tokens, autofill browser data, crypto wallet information, system fingerprints, VPN credentials, files, screenshots, and clipboard data.

5. Data exfiltration

• Once data is collected, the infostealer malware begins exfiltrating to the attacker‘s command and control (C2) server.
• Cybercriminals also exfiltrate data through Telegram bots, custom APIs, encrypted HTTP POST requests, and extensive botnet infrastructures.
• Many infostealers complete data exfiltration in under 3 seconds.

6. Clean up

• After the operation has been completed, infostealers delete themselves, remove temporary files, clear execution traces, and exit the system without persisting.
• Infostealer malware is stealthy, cleaning up after itself to reduce detection attempts.

7. Monetization

• Cybercriminals use stolen data to resell on the dark web.
• In some cases, the stolen data is used to launch further attacks, such as social engineering and ransomware attacks.
• Data sold on the dark web helps attackers to perform account takeovers, business email compromise (BEC), gain control of cloud environments, network intrusions using VPN access, and ransomware staging with stolen credentials.

Infostealer prevention tips

To prevent unauthorized access of personal devices and work accounts, security teams have to remain vigilant against cyber threats.

Infostealer detection is difficult, but there are warning signs to look out for.

Detection methods

1. Monitor for unexpected access requests to browser credential stores.
2. Check for outbound access to newly registered domains.
3. Detonate suspicious files in sandbox environments to reveal suspicious behavior.
4. Block unsigned executables from running.
5. Monitor for suspicious hijacking patterns like token reuse from unknown devices.
6. Scan the dark web for stolen credentials before hackers can use them.

Defensive measures

1. Block execution from Downloads, Temp, and User Profile paths.
2. Keep OS and browsers fully patched to harden endpoints.
3. Disable or restrict PowerShell, WScript, and macro execution where possible.
4. Reduce malware credential harvesting by disabling or restricting web browser password storage.
5. Use FIDO2 to avoid phishing attacks.
6. Monitor the dark web in real-time for stolen credentials.

How should incident response teams handle infostealer compromises?

If you notice any tell-tale signs of an infostealer malware infection, follow these steps to ensure you contain the spread.

• Revoke access: Disable the user’s access to internal systems and networks, then terminate all active session tokens to prevent these from being used by the threat actor.
• Investigate: Log any unusual IPs, devices, suspicious login times, and unusual access to sensitive files. Check for large file transfers and copying of confidential data.
• Remove the malware: Cybersecurity teams should clean the user‘s infected device, including both business and personal devices.
• Reset passwords: Ask the user to reset their password and ensure all passwords are stored on a secure password manager. Additionally, enforce MFA if it is not already being used.
• Harden your ecosystem: Prevent unmanaged devices from being used at work, shorten the duration of session tokens, monitor the dark web for stolen credentials, and raise employee awareness on the dangers of infostealers.

Wrapping up

Avoid being compromised by infostealers in 2026 by going beyond firewalls. Being compromised by infostealers can lead to data breaches, unauthorized access to internal systems, business email compromise (BEC), supply chain attacks, and ransomware attacks.

Vulnerabilities like outdated APIs give threat actors a foothold in your organization‘s ecosystem, leading to potentially devastating data breaches caused by infostealers.

Detect compromised credentials and exposed data with CybelAngel’s continuous dark web and infostealer monitoring

Dealing with infostealer compromises can be a strain on resources and lead to potentially damaging financial losses.

CybelAngel‘s Dark Web Monitoring helps your security teams better defend against infostealers. Our in-depth threat intelligence reports help teams better assess your organization‘s risk and alert you when stolen credentials are circulating.

Interested in a demo? See our solution in action with an expert member of our team.