Researchers Link the MARVEL_PRIME Dump to 51,992 Stolen Credentials on Telegram

HEROIC analysts identified the MARVEL_PRIME stealer log breach after researchers linked the dump to a Telegram upload in September 2023 that exposed 51,992 records. The compromised data includes email addresses, plaintext passwords, and URLs harvested from infected devices. MARVEL_PRIME is the original log in the series, and its scale of nearly 52,000 records makes it one of the larger individual Telegram stealer log distributions tracked in HEROIC's database.

Why MARVEL_PRIME uploaded by a Telegram User Is Dangerous

The sheer volume of records in MARVEL_PRIME makes it a significant resource for cybercriminals. With 51,992 plaintext credential pairs, attackers can run large-scale credential stuffing campaigns against popular services, expecting a meaningfull number of successful logins based on password reuse alone. The URLs included in the dump help attackers understand which services each victim was using, allowing them to prioritize high-value targets like banking sites and enterprise email accounts. Files of this size are often split into parts and redistributed, meaning MARVEL_PRIME PART 2 and other follow-up dumps may contain overlapping victims.

What Was Exposed in MARVEL_PRIME uploaded by a Telegram User

• Email Addresses
• Plaintext Passwords
• URLs

Why This Matters

A breach of nearly 52,000 records containing ready-to-use plaintext passwords is a serious event with real consequences for individuals and organizations alike. Credential stuffing powered by MARVEL_PRIME data can lead to widespread account takeovers, financial fraud, and identity theft. For businesses, a single compromised employee account can serve as an entry point for network intrusion, data theft, or ransomware deployment. Individuals face the loss of access to email, banking, and social accounts, often accompanied by fraudulent activity that takes months to resolve.

How Stealer Log Works

Researchers link large stealer log dumps like MARVEL_PRIME to organized infostealer campaigns where a single operator infects a large number of machines over a period of weeks or months. The malware silently collects saved credentials, cookies, and browsing history from each infected device and transmits the data to a central server. The operator then compiles the collected records into large files and uploads them to Telegram, either selling access or sharing them publicly to build credibility in criminal communities. The numbered parts structure of MARVEL_PRIME suggests a systematic approach to distributing the full dataset across multiple uploads.

Check If You Are Affected

Researchers have linked the MARVEL_PRIME dump to 51,992 stolen credentials on Telegram, and HEROIC has indexed the data so you can find out if you are among those affected. Use the free breach scanner at heroic.com to search HEROIC's database of over 400 billion records. If your email address appears in MARVEL_PRIME or any related breach, changing your passwords and enabling two-factor authentication can help prevent attackers from using your data against you. Don't wait untill its too late to take action.