How infostealers work

Infostealer malware usually arrives through fake software downloads, cracked applications, malicious adverts or phishing attachments. Once it runs, it gathers everything it can reach in a few seconds, packages it and sends it to the attacker's server. Common families have included RedLine, Raccoon, Vidar and Lumma. Many are sold as a service, so less skilled criminals can run their own campaigns.

What a stealer log contains

  • Usernames and passwords saved in browsers, with the URLs they belong to.
  • Session cookies and tokens, which can let an attacker take over a logged-in session.
  • Autofill data such as names, addresses and card details.
  • Screenshots, system information, IP address and installed software.

Why stealer logs are a business risk

When staff use personal or shared devices for work, or save work logins in a personal browser profile, an infection at home can expose corporate SSO, VPN, cloud and SaaS accounts. Because stolen cookies can carry an already-authenticated session, attackers may get in without needing the password or a second factor. Several large breaches have been traced back to a single stealer log containing one employee's credentials.

How to respond to a stealer log

  1. Revoke all sessions and tokens for the affected accounts, not only the password.
  2. Reset passwords for every account listed in the log.
  3. Identify and clean the infected device.
  4. Review sign-in logs for use of the stolen sessions.

How DarkInvader helps

DarkInvader's Leaked Credentials and Dark Web Monitoring watch for stealer log data linked to your domains, show which accounts and services are affected, and alert you so sessions can be revoked and devices cleaned quickly.

Explore Leaked Credentials

Frequently asked questions

What is the difference between a stealer log and a data breach?

A data breach usually exposes records from one organisation's database. A stealer log comes from one infected device and can contain credentials for many different services that person used, including work accounts.

Can stealer logs bypass MFA?

Sometimes. If the log includes a valid session cookie, an attacker can reuse the existing logged-in session without passing the MFA check again. Short session lifetimes and device-bound tokens reduce this risk.

Where are stealer logs sold?

On dark web marketplaces, criminal forums and Telegram channels, sometimes individually and sometimes in large bundles or subscription feeds.

Related terms and reading

Sources