Historical intelligence backfill. This assessment covers reporting originally published on 2025-10-22 and was added to the RWP archive on 2026-09-07.

Daily Top · OT

Nozomi's summer 2025 ransomware map is sensor alerts, not leak-site headcount

22 October 2025 — May was the loudest month in their sensors, BlackSuit on top, US 56 percent of malware-associated alerts, UK 14.5 percent. Do not add it to Dragos's industrial leak-site series.

RWP Ventures · 2026-09-07 · event 2025-09-01 · 1 min read · priority 7.0

Bottom line up front

CONFIRMED Nozomi Labs, 22 October 2025 — six-month sensor view of ransomware-related alerts, not a leak-site census. May was the peak month. BlackSuit led (CISA: Royal successor; Royal/Conti lineage; combined ransoms cited over $370M in CISA's telling as Nozomi quotes it). Black Basta in the top three; Nozomi notes the February leak pushed the gang quieter but leftover modules still alerted. Top countries by alert share: United States 56.42 percent, UK 14.53 percent. Attribution caveats: reused IPs, imprecise family labels. This is OT/IoT sensor noise, not "1,211 industrial victims." Dragos Q3/Q4 posts remain the leak-site series. Process/ICS Stage 2: not claimed.

Historical backfill of 22 October 2025 reporting; added 7 September 2026.

What happened

A Labs chart pack for spring/summer 2025 detections.

Why it mattered

Mixing sensor-alert share with leak-site victim counts is how briefings lie. Keep the units straight.

Who / what was affected

Nozomi's deployed sensors, English-speaking-heavy. Not a global victim registry.

Technical context

Hunt BlackSuit/Royal leftovers. Do not retire Black Basta detections because of a chat leak.

Exploitation / threat status at the time

CONFIRMED Nozomi alert mix.

REPORTED CISA lineage notes as quoted.

What defenders should have done

  1. Keep Royal/BlackSuit playbooks.
  2. Do not brief "56 percent US" as 56 percent of all ransomware.
  3. Read Dragos industrial counts alongside, not instead.

RWP assessment

Confidence: High as telemetry mix; low as industrial-impact measure.

Defensive actions

  1. Label the chart "sensor alerts."
  2. Identity + backups still beat a new family name.
  3. Next Nozomi ransomware post is a different quarter — do not merge.

Sources

  1. Nozomi Networks Labs — Mapping the ransomware landscape — summer 2025
  2. CISA — BlackSuit as Royal successor (as cited by Nozomi)
  3. Dragos — Q3 2025 industrial ransomware analysis