Breach Intelligence Report 21 Sep 2025

Monster Cloud Free 12 Oct 5 Stealer Log Breach: 25,194 US Records

HEROIC
HEROIC Threat Intelligence Team
Email Addresses Plaintext Password Urls
Your email may be in this breach. Check in 5 seconds — free, no signup required.
Scan Email →
Records Exposed 25,194
Source Type Stealer log
Origin Telegram
Password Type plaintext

Two Monster Cloud Free 12 Batches: The Oct 5 Entry with 25,194 Records

Monster Cloud's batch naming system has one notable complication: this dataset contains two distinct posts both titled "Monster Cloud Free 12." The first -- this one -- was released on October 5, 2023, and contains 25,194 records. The second, released on October 6, carries the same name but only 10,475 records. Whether this reflects a Telegram re-upload, a naming error in the original MC channel, a deliberate split batch, or simply two different promotionall releases given the same label is unclear. What is not ambiguous is the Oct 5 batch's 25,194 credentials: a substantial US stealer log collection, larger than any individual Monster Cloud batch released on Oct 6.


Monster Cloud Free 12 -- Oct 5 (October 2023): Stealer Log Summary

  • Records Exposed: 25,194
  • Data Types: Email addresses, plaintext passwords, URLs
  • Breach Type: Stealer log -- credentials harvested from malware-infected endpoints, not a direct database breach
  • Password Type: Plaintext -- captured directly from browser sessions and credential stores by infostealer malware
  • Country: United States
  • Date Leaked: October 5, 2023

Monster Cloud's Oct 5 Presence: Before the 30-Batch Surge

Monster Cloud is best known in this dataset for its October 6, 2023 release of 30 consecutive batches totaling 415,049 records. But the Oct 5 MC Free 12 batch confirms the operator was also active the day before -- either beginning a staged release sequence or re-releasing a previous collection under the same batch label. If Oct 5 MC Free 12 is counted alongside Oct 6's MC output, Monster Cloud's two-day credential exposure approaches or exceeds 440,000 US stealer log records. This scale further solidifies MC's position as the dominant operator in this dataset by volume.


25,194 Records: Scale and Immediate Risk

At 25,194 records, this batch is among the larger single releases in the Oct 5 dataset. It exceeds many individual Oct 6 MC batches in size, and is substanialy larger than its same-named Oct 6 counterpart (10,475). Every record in this collection is a plaintext credential set -- email, password, URL -- harvested directly from malware-infected US endpoints. No cracking step is required before these credentials become usable for credential stuffing. The risk to affected users is immediat and concrete: accounts associated with these email-password pairs are directly compromised unless passwords have been changed since October 2023.


Check If Your Data Was Exposed

HEROIC's free breach scanner searches across more than 400 billion exposed records -- including both Monster Cloud Free 12 batches and the full range of Oct 5-6 stealer log releases. Run a free scan at HEROIC's breach scanner to determine if your credentials appear in either batch.

Breach Breakdown

Domain N/A
Leaked Data Email Addresses,Plaintext Password,URLs
Password Types plaintext
Date Leaked 21 Sep 2025
Check in 5 seconds

25,194 passwords exposed. Is yours one of them?

Enter your email to scan this breach plus 400B+ other leaked records. If you're compromised, we'll show you exactly where and what to change.

All information submitted is Private and Secure. We do not sell or share email addresses. By searching, you agree to HEROIC's Privacy Policy and Terms of Service.

Free forever · No account required · Results in seconds

Private & Secure No Account Needed 3,653 scanned today
Breach Rank #N/A by affected users
Impact Score
1
sensitivity + scale + recency
Est. Financial Impact $182.3K fraud, phishing & misuse risk
Scan your email Free →
Scan to sign up

Scan to sign up instantly

24/7 Dark Web Monitoring
Instant Breach Alerts
Secure Data Protection
Your Data is at Risk

Your Personal Information is Exposed

We found your data exposed in multiple breaches. This includes:

  • Email addresses
  • Passwords
  • Phone numbers
  • Financial information
Secure My Information Now

Your information is protected by enterprise-grade security

Your Breach Details

Date:
Severity:
Records Exposed:

Your Exposed Information

Your Risk Level

How This Affects You

Full Breach Details

Premium Insights

Unlock Critical Security Information

Create a free account to access:

  • Full Breach Impact Analysis
  • Identity Theft Risk Score
  • Exposed Credentials Details
  • Personalized Security Recommendations
Create Free Account

Identity Theft Risk Score

Risk Score: 8.7/10 - Critical

Data Exposure Analysis

Passwords Critical
Financial High
Personal Medium
Social High
Security Critical

Breach Timeline Analysis

March 2024 Multiple credentials exposed in recent data breach
January 2024 Password found in dark web marketplace
December 2023 Personal information leaked in major security incident

Security Recommendations

High Priority
Password Security

Critical: Change compromised passwords immediately and enable 2FA on all accounts

Important
Financial Protection

Monitor credit reports and set up fraud alerts with major credit bureaus

Recommended
Identity Protection

Enable advanced identity monitoring and dark web surveillance