What Are Stealer Logs? The Silent Threat Stealing Your Passwords in 2026

You might have strong passwords, two-factor authentication enabled, and a cautious approach to clicking links. But a growing class of malware called infostealers can silently extract every credential saved in your browser in seconds, and you would never know it happened.

In 2025, infostealer malware was responsible for stealing 1.8 billion credentials globally. The stolen data, packaged into files called stealer logs, is then sold on dark web marketplaces and Telegram channels for as little as a few dollars per victim.

This guide explains what stealer logs are, how infostealer malware works, and most importantly, how you can check if your data has been compromised.

What Is Infostealer Malware?

Infostealer malware (also called info-stealing trojans) is a category of malicious software designed to extract sensitive data from infected devices. Unlike ransomware that locks your files, infostealers operate silently, stealing data without any visible symptoms.

A single infostealer infection can extract:

• All saved passwords from Chrome, Firefox, Edge, and other browsers
• Session cookies that allow attackers to bypass two-factor authentication
• Credit card numbers saved in browser autofill
• Cryptocurrency wallet seeds and private keys
• Discord, Telegram, and gaming tokens
• VPN credentials and saved Wi-Fi passwords
• System information including IP address, OS version, and installed software

How Do Infostealers Spread?

Infostealers reach victims through several common vectors:

1. Fake software and game cracks: Pirated software, fake game cheats, and cracked tools are the #1 delivery method. The "free" software works as expected while the stealer runs invisibly in the background.
2. Phishing emails: Emails impersonating banks, shipping companies, or employers contain malicious attachments or links that download the stealer.
3. Malvertising: Legitimate-looking ads on search engines redirect to malicious download pages. Attackers even buy Google Ads for popular software names.
4. Malicious browser extensions: Fake extensions that promise useful features while stealing browser data.
5. YouTube and social media: Tutorial videos linking to "tools" in the description that are actually infostealers.

The Major Infostealer Families in 2026

The infostealer landscape is dominated by a handful of malware families, most operating under a Malware-as-a-Service (MaaS) model where criminals rent access for as little as $200/month:

Stealer	Status	Known For
Lumma Stealer	Active (dominant in 2025-2026)	Advanced evasion, targets crypto wallets
RedLine Stealer	Disrupted by law enforcement in 2024, variants still active	Most widely distributed stealer historically
Raccoon Stealer	Active (v2)	User-friendly dashboard, broad targeting
Vidar Stealer	Active	Sold via Telegram, targets 2FA apps
Stealc	Active	Modular design, C2 communication

What Are Stealer Logs?

A stealer log is the output file generated by infostealer malware from a single infected device. Think of it as a complete digital snapshot of the victim, containing:

• A text file with all extracted credentials (URL, username, password)
• Browser cookie files (which can be imported to hijack active sessions)
• Credit card data from autofill
• Screenshots of the victim's desktop
• System information (IP, country, hardware specs)

These logs are sold in bulk on dark web markets. A fresh log with banking credentials might sell for $5-50, while logs containing corporate VPN access can fetch hundreds of dollars.

The Scale of the Problem

• 46% of stealer logs contain corporate credentials alongside personal ones
• 54% of ransomware victims had their domains appear in infostealer credential dumps before the attack
• 35.7% of infected machines are personal, unshared computers
• Over 13.2 billion credentials were collected from stealer logs in 2024 alone

How Stealer Logs Bypass Two-Factor Authentication

One of the most dangerous aspects of infostealers is their ability to bypass 2FA completely. Here is how:

When you log into a website with 2FA, the site generates a session cookie that keeps you authenticated. This cookie is stored in your browser. Infostealer malware extracts these cookies along with your passwords.

An attacker can then import your stolen cookie into their own browser and gain full access to your account without ever needing your password or 2FA code. This technique is called a pass-the-cookie attack, and it works on almost every website including Google, Microsoft 365, banking portals, and social media.

How to Check If Your Credentials Are in Stealer Logs

Unlike traditional data breaches that are often reported publicly, stealer log data circulates on underground markets. Most victims never discover they have been compromised until an account is taken over.

You can proactively check your exposure using specialized tools:

1. Intelligence Security Stealer Log Search – Search across millions of stealer logs by email, domain, or username. See exactly which credentials were extracted and from which device.
2. Session Cookie Search – Check if your active session cookies have been stolen, enabling pass-the-cookie attacks.
3. Email Breach Check – Comprehensive search across breach databases and stealer log collections.

What to Do If You Find Your Data in Stealer Logs

1. Change all passwords immediately – Start with email, banking, and any accounts that share the compromised password. Use a password manager to generate unique passwords.
2. Invalidate all sessions – Log out of all devices on every account (most services have a "sign out all devices" option). This invalidates stolen cookies.
3. Run a full antivirus scan – The infostealer may still be active on your device. Use a reputable antivirus with real-time protection.
4. Enable hardware 2FA – If possible, switch to hardware security keys (YubiKey, Titan) which are resistant to session hijacking.
5. Monitor your accounts – Watch for unauthorized logins, password reset emails, and unfamiliar transactions for the next several months.
6. Check for unauthorized access – Review login histories on critical accounts (Google, Microsoft, banking) for suspicious locations or devices.

How to Prevent Infostealer Infections

• Never download cracked software – This is the #1 infection vector. If software costs money, pay for it or use a free alternative.
• Be cautious with email attachments – Even from known contacts, verify unexpected attachments through a separate channel.
• Use a password manager instead of browser autofill – Dedicated password managers like Bitwarden or 1Password are harder for infostealers to extract from than browser-stored credentials.
• Keep your browser and OS updated – Many infostealers exploit known vulnerabilities in outdated software.
• Install a reputable endpoint protection tool – Modern antivirus with behavioral detection can catch infostealers before they exfiltrate data.
• Verify software downloads – Only download from official websites. Check that URLs are correct before downloading.

Frequently Asked Questions

Can infostealers steal passwords from a password manager?

Standalone password managers (Bitwarden, 1Password, KeePass) are significantly harder to attack than browser-stored passwords. However, if the master password is stored in the browser or the password manager browser extension has an active session, some advanced stealers may extract it. Always lock your password manager when not in use.

How long do stolen credentials remain useful?

Passwords remain valid until changed by the user. Session cookies typically expire within days to weeks, but some services maintain long-lived sessions. This is why immediate password changes and session invalidation are critical after a compromise.

Is my data in stealer logs even if I have not been hacked?

Yes. If someone else who has your email address and a shared password was infected, your credentials could appear in their stealer log. Credential reuse across sites amplifies this risk enormously.