The WATERCLOUDz Telegram Log Means Someone Could Be Logging Into Your Accounts

HEROIC analysts identified the WATERCLOUDz stealer log dataset, a collection of 756 files uploaded to Telegram in September 2023. The dump exposed 8,212 records containing email addresses, plaintext passwords, and URLs scraped from infected devices. This dataset is part of a larger wave of stealer log activity that circulated through private Telegram groups under the label "Big Club," suggesting organized distribution among cybercriminal networks.

Why This Is Dangerous

Plaintext passwords are immediately usable -- there is no cracking required. Attackers who access this data can attempt logins across email providers, cloud storage platforms, financial services, and social networks right away. The combination of email addresses and the specific URLs from which credentials were stolen tells attackers exactly where each victim has accounts. This makes credential stuffing campaigns highly efficient and targeted. Victims may not recieve any alert until unauthorized access has already occured.

What Was Exposed

• Email Addresses
• Plaintext Passwords
• URLs

Why This Matters

This kind of breach enables account takeover at scale. Once attackers have working credentials, they can access bank accounts, drain digital wallets, impersonate victims in emails, and lock people out of their own accounts by changing passwords and recovery information. Identity theft can follow quickly, with attackers using personal information to open new credit lines or make fraudulent purchases. Stealer log data is also regularly resold, meaning your information can end up in the hands of multiple criminal groups over time.

How Stealer Log Breaches Work

Information stealer malware is designed to run silently on a victims device while harvesting credentials and browsing data. The most common infection routes include phishing emails with malicious attachments, fake software cracks or game cheats downloaded from unofficial sites, and trojanized browser extensions. Once the malware is active, it extracts saved passwords, session tokens, and form-fill data, then packages everything into log files. These files are uploaded to command-and-control servers or shared directly in private Telegram channels, where cybercriminals trade or sell them in bulk packages like the 756-file WATERCLOUDz collection.

Check If You Are Affected

Your credentials from this stealer log could be in active use by attackers right now. HEROIC provides a free personal data scanner that searches across more than 400 billion exposed records to tell you if your information has been compromised. Checking your exposure is a definately smart first step. Visit HEROIC to run a free scan and find out if your data appeared in the WATERCLOUDz dump or any other known breach.