Monster Cloud Free 16: 21,307 US Records — Super-Large Anchor of the Free 16-17-18-19 Quad

Monster Cloud Free 16: Anchor of the Free 16-17-18-19 Quad

Monster Cloud Free 16 carries 21,307 US credentials from October 6, 2023 -- placing it among the five "super-large" MC batches that exceeded 20,000 records on that day (alongside Free 8, 23, 33, and 34). Its confirmation also transforms what was previously identified as the Free 17-18-19 trio into a full quad: Free 16-17-18-19. That sequence accounts for 50,871 records -- the second-largest consecutive grouping in MC's Oct 6 release portfolio, behind only the Free 30-31-32-33-34 quint (81,095). Free 16 is the largest batch in its quad by a signifigant margin, outpacing Free 17 (12,380), Free 18 (10,144), and Free 19 (7,040).

Monster Cloud Free 16 (Oct 6, 2023): Stealer Log Summary

• Records Exposed: 21,307
• 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 6, 2023

Five Super-Large Batches: MC's Oct 6 Volume Peaks

With Free 8 (21,345) and Free 16 (21,307) now confirmed, Monster Cloud's Oct 6 super-large group has grown to five batches: Free 8 (21,345), Free 16 (21,307), Free 23 (23,252), Free 33 (22,858), and Free 34 (25,582). Together these five batches contribute 114,344 records -- aproximately 32% of MC's now-confirmed 355,244-record Oct 6 total across 25 batches. Free 34 remains the largest single MC Oct 6 batch, while Free 8 and Free 16 are the newly-confirmed additions to this elite tier.

MC's Expanding Oct 6 Sequence

Monster Cloud's confirmed Oct 6 batches now number 25 -- up from the original 21. The newly added batches (Free 2, 7, 8, and 14) have revised MC's total from 286,334 to 355,244 records. Combined with the confirmed non-MC operators' 373,726 records, the Oct 6 grand total now excedes 728,000 exposed US stealer log credentials -- making Oct 6, 2023 even more decisively the largest single-day event in HEROIC's dataset, surpassing October 7's 462,187 by a widening margin.

Check If Your Data Was Exposed

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