MAY 4 – 3847 LOGS: 81,191 Stealer Log Records From a Coordinated Telegram Dump

MAY 4 -- 3847 LOGS: The Largest Batch in a Coordinated September 2023 Stealer Dump

At 81,191 records compiled from 3,847 infected devices, the MAY 4 -- 3847 LOGS batch is the largest individual component of the September 2023 stealer dump series that hit Telegram on September 26, 2023. The same actor who distributed the 794-log and smaller batches also released this one -- same date, same channel, same format. The combined operation across miltiple batch files represents a single coordinated infrastructure clearance: an actor releasing months of accumulated harvest before cycling to a new collection campaign.

MAY 4 - 3847 LOGS (September 2023): Breach Summary

• Records Exposed: 81,191
• Data Types: Email addresses, plaintext passwords, endpoint URLs, API hosts
• Breach Type: Stealer log
• Country Affected: United States
• Date Leaked: September 26, 2023

How 81,191 Records Get Processed After a Telegram Upload

When a batch this large hits Telegram, it doesn't sit unprocessed for long. Automated credential-testing tools can ingest 81,191 email/password pairs and begin stuffing them against target platforms within minutes of download. More sophisticated actors run the URL data through parsing pipelines to categorize targets by service type -- separating cloud platform credentials from financial service credentials from corporate VPN credentials -- before running targeted credential stuffing against the highest-value targets. The most eficciently run operations will have checked the freshest, highest-value credentials against tier-1 targets within hours of the Telegram upload going live.

The API Host Exposure at Scale

With 3,847 compramised devices in this batch, the API host data covers an enormous range of services. Developers who had infostealer malware on work machines around May 4, 2023 may find their API keys, database connection strings, cloud console credentials, and CI/CD tokens represented in this dump alongside their personal email passwords. The URL data turns a credential dump into a target directory -- attackers know not just what the password is, but exactly which systems it unlocks. At 81,191 records, the probability that this batch contains at least some enterprise infrastructure credentials is extremely high.

A Single Actor's May 2023 Collection Made Public

The batch-and-release pattern visible across the September 26, 2023 upload series -- MAY 4 batches of 794 and 3,847 logs, MAY 5 batch of 2,407 logs -- suggests a single operation that ran continuous collection through at least May 2023, then held the compiled inventory until September before public release. This timeline means affected users went an average of four months without knowing their credentials were compromised. During that window, the actor could have been monetizing the freshest credentials privately before dumping the remainder publicly. The September 2023 release represents the tail end of that exploitation cycle, not the beginning.

Check If Your Credentials Were Exposed

HEROIC's free breach scanner searches across more than 400 billion exposed records to tell you exactly which of your accounts have been compromised. With 81,191 records from 3,847 infected devices, this is one of the larger stealer log batches in the September 2023 series. Check now at HEROIC.com -- your credentials may have been in active use since May 2023.