The LeakBase 50Kk ULP by perjudica Means Someone Could Be Logging Into Your Accounts Right Now

On December 21, 2024, a threat actor known as perjudica posted a stealer log titled "50Kk ULP" on a major underground hacking forum. The file contained 50 million total records, from which 12,580,631 unique email addresses were identified, each paired with a plaintext password and the URL of the website the password was used on. This is not a breach of a single company. It is a compiled credential dump built from infostealer malware infections across many victims and many websites. The result is a massive, immediately usable list of real people's login combinations, available to anyone willing to download it. This dump was posted the same day as a related credential release: LeakBase 10Kk ULP by farmagol, which exposed an additional 2.38 million accounts with plaintext passwords.

Why This Is Dangerous

With over 12.5 million plaintext credentials in a single file, this log gives attackers a ready-to-use arsenal for account takeover at scale. They do not need to crack anything. Every entry in this file is a working username-and-password pair, tied to a specific website. Credential stuffing tools can cycle through millions of these combinations automatically, testing them against banks, email providers, streaming services, and corporate logins. Users who reuse passwords across multiple sites are especially vulnerable: one exposed password can unlock accounts they never knowingly connected to the source of the breach.

What Was Exposed

• Email Address
• Plaintext Password
• HomePage URL (the site the password belongs to)

Why This Matters

When an attacker finds a working match between this credential list and a live account, they can take control of that account instantly. From there, the consequences range from drained financial accounts and fraudulent purchases to identity theft and account lockout. Email accounts are a particularly high-value target because they serve as recovery mechanisms for everything else. A compromised email account lets an attacker reset passwords across every other service linked to it. This is how a single entry in a stealer log can cascade into a full-scale identity compromise.

How Stealer Log Credential Dumps Work

Infostealer malware spreads through phishing emails, pirated software, malicious browser extensions, and compromised websites. Once installed on a victim's device, it operates silently, capturing saved passwords from browsers, cookies, and active login sessions. The stolen data is transmitted to the attacker and compiled into logs organized by URL and credential. These logs are then sold or shared on underground forums, giving other attackers immediate access to millions of verified credentials without having to breach any company directly. The victim whose device was infected may never know their passwords were captured.

Check If You Are Affected

HEROIC's free breach scanner checks your email address against more than 400 billion exposed records, including this LeakBase 50Kk ULP by perjudica dump. If your credentials appear in this file, the time to act is now, before an attacker uses them. Scan your email for free at HEROIC and change any password that has been exposed.

Related Parts of This Breach Series

This dump was posted on the same day as another large ULP stealer log release on LeakBase:

• LeakBase 10Kk ULP by farmagol — 2.38 million unique plaintext credentials, posted December 21, 2024