atcmail.com: 1,346 Stolen Login Credentials Hit the Dark Web

HEROIC analysts identified this stealer log on 10-Jun-2026. The breach exposed 1,346 records, with stolen data including email addresses, plaintext passwords, and URLs. The source is identified as atcmail.com.

Why This Is Dangerous

Each of the 1,346 records in this breach contains an email address, a plaintext password, and a URL pointing to the account it belongs to. Because the passwords are stored in plaintext, they can be used immediately to attempt unauthorized access. Victims have no encryption barrier protecting their credentials from anyone who accesses this dataset.

What Was Exposed

• Email Addresses
• Plaintext Passwords
• URLs

Why This Matters

Credential theft of this type fuels credential stuffing attacks, where cybercriminals systematically test stolen login pairs across popular services. This practice is particularly effective against people who reuse the same password on multiple accounts. A single compromised credential can result in account takeover across banking, social media, and email platforms, as well as identity theft and financial loss.

How a Stealer Log Works

An infostealer is a type of malware designed specifically to extract login credentials from infected devices. It typically spreads through phishing messages, cracked software, or fake browser extensions. Once on a device, the malware silently reads saved passwords from browsers, captures login activity in real time, and sends the collected data to the attacker. That data becomes a stealer log, which is distributed through Telegram and dark web forums.

Check If You Are Affected

HEROIC offers a free breach scanner that searches 400 billion records. Search your email address now to see if your credentials appear here or elsewhere. Free, takes seconds.