Inside Mail Access Mix Stealer Logs: 171,926 Passwords Harvested

HEROIC security researchers have cataloged a large stealer log collection titled Mail Access Mix that appeared on a public Telegram channel in June 2026. The file contains 171,926 records — each consisting of an email address paired with a plaintext password and the URL of the service where the credentials were entered. This is one of the larger single-file stealer log uploads observed in recent months, and the "Mail Access" designation indicates the data has been filtered to prioritize email account credentials.

At nearly 172,000 records, this collection represents a substantial intelligence asset for cybercriminals. The credentials were harvested by infostealer malware from individual devices and compiled into a single distributable file now available to anyone on Telegram.

Why Plaintext Passwords Are the Most Exploitable Data Type

From a technical standpoint, plaintext passwords represent the worst-case scenario for exposed credentials. When passwords are stored as bcrypt, scrypt, or argon2 hashes, attackers face significant computational barriers. Plaintext credentials bypass all of these protections entirely.

The 171,926 passwords in this dump can be loaded directly into credential testing frameworks like Sentry MBA or OpenBullet. These tools automate login attempts across hundreds of target websites simultaneously, testing each email-and-password pair in seconds. With plaintext data, there is no preprocessing step — the attack pipeline starts immediately.

For email accounts in particular, the consequences are severe. A compromised email inbox serves as an authentication oracle, allowing attackers to reset passwords and intercept verification codes for every service linked to that address.

What Was Exposed in the Mail Access Mix Dump

• Email Addresses — A diverse collection of email accounts spanning multiple providers, harvested from the browser credential stores of infected devices across the United States.
• Plaintext Passwords — Raw passwords captured by infostealer malware at the moment of entry or extraction from saved credential databases, with no hashing or encryption applied.
• URLs — The specific login endpoints where credentials were used, providing a technical fingerprint of each victim's service usage and enabling precise, targeted attack campaigns.

Why 171,926 Records Create an Industrial-Scale Threat

The sheer volume of this dump elevates it from a targeted threat to an industrial-scale attack resource. At 171,926 records, even a modest success rate in credential stuffing campaigns would yield thousands of compromised accounts. A 2% hit rate — typical for fresh stealer log data — would translate to roughly 3,400 successful account takeovers.

Large datasets like Mail Access Mix are also frequently incorporated into composite credential lists that aggregate millions of entries from multiple sources. Once merged into these master lists, the records gain a longer shelf life and wider reach, continuing to pose threats for years after the initial upload.

The economic value of nearly 172,000 verified email credentials is substantial in underground markets. Bulk email account access is used for spam campaigns, phishing infrastructure, cryptocurrency theft, and business email compromise schemes that can generate millions in fraudulent transactions.

How Stealer Logs Are Compiled at Scale

A dump of this size was not created from a single infected machine. Mail Access Mix represents the aggregated output of infostealer campaigns affecting thousands of individual devices. Malware variants like RedLine, Raccoon, and Vidar infect devices through malicious ads, fake software downloads, and phishing attachments, then exfiltrate credential databases to centralized collection servers.

Operators of these campaigns typically sell raw logs in bulk to intermediaries who sort, filter, and repackage the data. The "Mail Access" label indicates this collection has been processed to extract email-specific credentials from a larger pool of stolen data, increasing its utility for attackers focused on email account compromise.

The final product is distributed through Telegram channels that specialize in credential data. Subscribers receive regular uploads and can download collections like Mail Access Mix within minutes of posting. The speed of distribution means that by the time a dump is discovered by security researchers, it has already been downloaded and weaponized by numerous threat actors.

Check If Your Credentials Appear in This Leak

With 171,926 records in this single collection, the statistical likelihood of any regular email user being affected is meaningful. If you have ever saved passwords in your browser or downloaded software from unofficial sources, your credentials could be among those harvested by infostealer malware.

HEROIC maintains a free breach scanner backed by more than 400 billion records from breaches and stealer log distributions worldwide. Search your email address to determine whether your credentials appear in the Mail Access Mix dump or in any other compromised dataset. If exposed, change your email password immediately, audit all accounts linked to that address, and enable two-factor authentication everywhere it is available.