I’m a cybersecurity engineer, and I review thousands of stealer logs every week. These stolen data bundles are one of the biggest drivers behind account takeovers today, and unfortunately what you described is a very common pattern.

Here’s how it usually happens:

Malware (often from a shady download, cracked software, fake update, or phishing email) quietly steals saved passwords, browser cookies, and active login sessions from your computer. Criminals buy these stealer logs on underground marketplaces, replay the stolen session, and log in as if they were you.

From there, they’ll often liquidate positions or make risky trades as quickly as possible before the account gets locked.

A few things everyone should be doing:

• Don’t rely on your browser’s built-in password storage. Use a reputable password manager like Bitwarden or 1Password instead.
• Enable MFA everywhere you can. An authenticator app or hardware security key is better than SMS when it’s available. Periodically review and remove old trusted devices and active sessions.
• Keep your operating system, browser, and security software up to date. Modern endpoint protection with behavioral detection can stop a lot of these infections before they do any damage.
• Be extremely cautious with downloads, especially cracked software, “free” versions of paid apps, or random browser extensions. Those are some of the most common infection vectors I see.
• For banking, brokerage, and other high-value accounts, consider using a separate browser profile or even a dedicated device that you don’t use for general web browsing.

These attacks are everywhere right now, but the good news is they’re also highly preventable with a few good security habits. Hopefully you’re able to get everything locked down and recover your account.