The ARCEUSULP 137 Leak Could Let Hackers Into Your Accounts

HEROIC analysts identified this stealer log on 20-Jun-2026. The breach exposed 2,436,419 records, with stolen data including email addresses, plaintext passwords, and URLs. The source is identified as ARCEUSULP 137.

Why This Is Dangerous

With over 2.4 million plaintext passwords and matching email addresses now in the hands of cybercriminals, attackers can attempt to access email inboxes, social media accounts, and banking portals in bulk using automated tools. Because the passwords are not encrypted, there is no delay between obtaining the data and attempting account takeovers. The URLs included in this log tell attackers exactly which sites each victim used.

What Was Exposed

• Email Addresses
• Plaintext Passwords
• URLs

Why This Matters

A breach of this size gives criminals a wide net to cast. Automated credential stuffing tools can test millions of username and password combinations across hundreds of websites in a matter of hours. Even if you only reuse your password on one other site, that may be enough for an attacker to gain access. The ARCEUSULP 137 leak increases the overall volume of stolen credentials circulating in criminal communities, raising the risk for everyone whose data appears in it.

How a Stealer Log Works

A stealer log is produced by malware that infects a victim's device through a malicious file download or phishing link. Once active, the malware captures passwords stored in browsers and applications, records website URLs, and sends this data to the attacker as a bundled log file. These files are then shared in private Telegram groups and dark web forums where they are used to carry out account takeovers.

Check If You Are Affected

HEROIC offers a free breach scanner that searches 400 billion records from known breaches. Search your email address now to find out if your credentials appear in this breach or others. The scan is free and takes seconds.