The Basediller URL-Log-Pass 87 Leak Holds More Stolen Logins Than a Mid-Sized City Has Residents

HEROIC analysts verified the Basediller URL-Log-Pass 87 combolist as part of our ongoing dark web monitoring operation. Uploaded to Telegram in July 2024, this file contained 529,168 records, each pairing an email address with a plaintext password and the URL of the site where that credential was originally used. The dataset was distributed anonymously and is consistent with stealer log compilation methods widely used by credential theft actors.

Why URL-Paired Credentials Are More Dangerous Than Ordinary Leaks

When a stolen credential file includes the target URL alongside the email and password, attackers gain a significant operational advantage. They do not need to test credentials across thousands of websites hoping for a match. Each record in this file already tells them exactly where to log in. That precision makes the Basediller URL-Log-Pass 87 dataset considerably more useful to attackers than a standard credential dump, and considerably more dangerous for the people whose data appears in it.

Plaintext passwords add another layer of risk. Hashed passwords require cracking tools and time. These do not. Every record is ready to use as-is.

What Was Exposed

• Email addresses
• Plaintext passwords
• URLs (the specific login pages associated with each credential)

Why This Matters: Credential Stuffing, Account Takeovers, and Beyond

Combolist files like this one power automated credential stuffing campaigns. Attackers load the file into tools designed to attempt logins at scale across banking sites, e-commerce platforms, email providers, and social media. A single successful login can unlock much more than the original account, especially when that account is used to reset passwords elsewhere.

The downstream risks extend to identity theft and financial fraud. If a compromised email account is used as a recovery address for a bank or investment account, attackers can trigger resets and drain funds before the victim knows their email was accessed. This is not a theoretical chain of events. It is one of the most common fraud patterns seen following large combolist exposures.

How Combolist Files Are Built and Shared

A combolist aggregates credentials from multiple sources into a single formatted file. The inputs typically come from prior data breaches, phishing campaigns, and malware that records keystrokes or harvests saved browser passwords. The URL-Log-Pass format, used in this file, is specifically designed for use with account checking tools, making it one of the more immediately weaponizable combolist formats in circulation.

Telegram channels have become the distribution backbone for these files. Threat actors upload them to private and semi-private channels where other criminals download, trade, and further distribute them. The Basediller series specifically represents a continuing sequence of uploads from the same source channel, indicating an organized and ongoing credential harvesting operation.

Check If Your Credentials Appear in This Breach

HEROIC's free breach scanner indexes more than 400 billion records, including datasets from the Basediller combolist series. Enter your email address to find out if your credentials appear in this file or any other verified breach in our database. Knowing what was exposed is the first step toward protecting your accounts. If your email appears, change the affected password immediately and turn on two-factor authentication everywhere it is offered.