Most people picture a data breach as a company losing a list of emails and hashed passwords. Stealer logs are a different, more personal problem. So what are stealer logs? A stealer log is the package of data that infostealer malware copies off a single infected computer or phone and uploads to whoever controls it. Instead of one leaked password, a single log can contain every password saved in your browser, your autofill data, and the session cookies that keep you signed in. Understanding how this works is the first step to knowing whether your accounts are still safe.
What infostealer malware actually does
An infostealer is a small program built to grab sensitive data and leave. The best-known families are RedLine, Vidar, and Raccoon, but there are dozens of others, and new ones appear constantly. Once the program runs on your device, it works through the places where useful information tends to sit. It reads the passwords your browser has saved, the autofill data you use to complete forms (names, addresses, sometimes card details), and the cookies that keep you signed in to websites.
Infostealer malware usually collects more on top of that: a list of installed programs, screenshots of the desktop, files from common folders, and details about cryptocurrency wallets. All of it is bundled into a single package, the "log," and uploaded to the attacker. The whole process can take a few seconds and normally leaves no obvious sign that anything happened.
The main infostealer families
Most stealer logs in circulation come from a handful of malware-as-a-service families. RedLine and Vidar have dominated for years and are still responsible for a large share of the logs traded on Telegram channels and criminal forums. Raccoon Stealer, Lumma (LummaC2), StealC, and Meduza round out the current top tier. Operators rent these tools to affiliates for a flat monthly fee, so the barrier to running a campaign is low and the volume of fresh logs is enormous. The specific family matters because each one targets slightly different browsers, wallets, and apps, but from a victim's point of view the outcome is identical: passwords and session cookies leave the device.
Why a stealer log is worse than a normal breach: session cookie theft
When a company is breached, you typically lose a password that was at least scrambled, and changing it fixes the problem. A stealer log is more dangerous because of one item in particular: session cookies.
A session cookie is the small token a website gives your browser after you log in, so you don't have to type your password on every page. Session cookie theft is what makes stealer logs so valuable. If an attacker loads a valid session cookie into their own browser, the site treats them as you, already signed in. They skip the login screen entirely, which means they also skip multi-factor authentication. Your second factor only protects the moment of logging in, and a stolen session is already past that point.
So a stealer log can hand someone live access to your email, banking, social media, or work accounts even if you used a strong password and had MFA turned on. Because the log also contains your saved passwords in readable form, it gives an attacker both the keys and a way around the locks.
How devices get infected with infostealer malware
Infections almost always come from running something you shouldn't have. The most common source is cracked or pirated software: a "free" version of a paid program, a game crack, or a license-key generator. These files are a natural disguise for malware because the person downloading them already expects to bypass a warning to run them.
Other routes include fake software updates, attachments in convincing emails, links in YouTube descriptions or Discord messages promising free tools, fake browser CAPTCHA prompts that ask you to paste a command, and downloads from sites that imitate a real product's homepage. The common thread is a file you chose to open. Infostealers rarely break in on their own; they rely on someone clicking "run."
How to run a stealer log check on your own exposure
You can't tell from the device itself whether your data has already been sold or shared, because the malware's job is to stay quiet. What you can do is run a stealer log check: search the collections of stealer logs that have been leaked or traded and see whether your identifiers appear. Revealer searches 38 billion+ records, including data pulled from these logs, so you can look up your own email address and see whether it shows up. Check your exposure against the info stealer logs dataset directly, or run a broader data breach lookup to see every leak tied to your address.
If your details show up, treat the device they came from as compromised until you've cleaned it.
How to clean up after a stealer log infection
Start by changing your important passwords, but do it from a device you trust, not the one you suspect is infected. Change email and banking first, since those are used to reset everything else. Then sign out of all sessions everywhere you can; most major services have a "log out of all devices" option, which invalidates stolen session cookies.
Run a full scan with reputable antivirus software, and if you ran cracked software or you're unsure, consider wiping and reinstalling the operating system rather than trying to find every trace by hand. Stop saving passwords in the browser and move to a dedicated password manager, and remove any pirated software for good.
Stealer log FAQ
What are stealer logs, in one sentence?
A stealer log is the bundle of passwords, cookies, autofill data, and device details that infostealer malware copies from one infected machine and hands to an attacker.
How do I check if I'm in a stealer log?
You can't detect it reliably from the infected device itself. Run a stealer log check by searching leaked log collections for your email address. Revealer's info stealer logs search covers data pulled from these logs across 38 billion+ records.
Do stealer logs bypass two-factor authentication?
Yes, indirectly. Session cookie theft lets an attacker resume a session you already authenticated, so they never reach the login screen where MFA is enforced. Signing out of all devices invalidates those stolen sessions.
What are RedLine and Vidar?
RedLine and Vidar are two of the most common infostealer malware families. Both harvest browser passwords, cookies, and wallet data, and both are sold as a service, which is why their logs make up so much of what circulates on underground markets.
Can antivirus remove infostealer malware?
A reputable scan can remove many infections, but because a stealer may have already exfiltrated your data, the safest response after a confirmed infection is to reset passwords from a clean device and reinstall the operating system.
If you want to know whether your email or passwords already appear in circulating stealer logs, search the info stealer logs page on Revealer and act on whatever you find.