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Cybersecurity: Threats and Defences
3AUG

Ransomware tempo holds at 95 in May

3 min read
16:08UTC

BlackFog counted 95 publicly disclosed ransomware attacks in May across 17 countries, the US taking 54 and Australia 18. Qilin led with 11 victims among 37 active groups, with no sign of consolidation.

TechnologyDeveloping
Key takeaway

May ran 95 disclosed ransomware attacks across 37 active groups, with healthcare hit hardest and no consolidation in sight.

BlackFog counted 95 publicly disclosed ransomware attacks worldwide in May 2026 across 17 countries, the United States taking 54 and Australia 18, so the monthly tempo held even as enforcement intensified 1. The security vendor compiles its figures from leak-site postings and public disclosures, which capture the visible floor of activity rather than the full total.

Healthcare was the hardest-hit sector with 28 incidents, because care delivery cannot tolerate downtime, so hospitals pay faster and crews target them first 2. Qilin led all crews with 11 claimed victims, but the more telling figure is the 37 active groups running in a single month with no sign of consolidation 3.

That group count is why the takedown headlines do not translate into falling risk. When US prosecutors unsealed Scattered Spider charges against Peter Stokes in April , they took an individual actor off the board without thinning the ecosystem around him. The bottleneck on the criminal side is the supply of affiliates, the freelance operators who rent a crew's tooling and split the proceeds, and neither an arrest nor a server seizure reduces that pool. For a defender, the lesson is that enforcement wins should not be read as a drop in operational threat; the tempo is the planning baseline, not the takedown.

Deep Analysis

In plain English

Ransomware attacks happen when criminals break into an organisation's computer systems, scramble all the files so the organisation cannot access them, and then demand money to restore access. Sometimes they also steal the files first and threaten to publish sensitive information if the ransom is not paid. BlackFog, a security company that tracks these attacks, counted 95 publicly known ransomware incidents in May 2026 across 17 countries. Healthcare was the hardest hit sector, with 28 hospitals and medical organisations affected. The US accounted for more than half of all known victims. A group called Qilin led all criminal ransomware operators with 11 claimed attacks, one of 37 active groups operating during the month.

What could happen next?
  • Risk

    Healthcare organisations running unpatched legacy infrastructure in the US and Australia face near-term ransomware targeting by Qilin affiliates, given the group's documented sector preference and the disproportionate victim counts in both countries.

  • Consequence

    The absence of consolidation in the 37-group ecosystem means law-enforcement takedowns of individual groups, including the Operation Saffron disruption of First VPN, redistribute affiliates rather than reducing attack volume.

First Reported In

Update #6 · The 2024 patch that is breaking now

BlackFog· 7 Jun 2026
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Different Perspectives
Group-IB
Group-IB
Group-IB, headquartered in Singapore, documented on 19 March that The Gentlemen began inside Qilin's own affiliate programme and split from it over a payment dispute. Its analysis makes this window's leak-site tally readable as a fracture inside one ransomware operation rather than the arrival of an unknown crew.
ENISA
ENISA
ENISA placed EU drinking water and wastewater in its cyber risk zone for the first time on 28 May, finding one in three water entities had never run a risk assessment. CISA's 30 July advisory to American operators reads as the operational sequel to a gap European regulators had already documented two months earlier.
House of Lords and NCSC
House of Lords and NCSC
The Cyber Security and Resilience Bill sits at House of Lords committee stage, its amendment paper running to 23 July. Separately, the NCSC guidance CISA cited when directing water operators to disconnect controllers is version 1.0 from March 2024, a two-year-old British document doing operational work in an American alert published last week.
heise online
heise online
heise online reported on 27 July that Russian state attackers, named as APT28, ran the hotel WiFi credential-harvesting campaign. Its attribution is firmer than ReliaQuest's own hedged low-to-medium confidence assessment of the same intrusion, a difference in national reporting posture rather than a settled dispute over who is responsible.
CISA and ReliaQuest
CISA and ReliaQuest
CISA compressed remediation deadlines under BOD 26-04 while, in the same window, telling water and wastewater operators to disconnect internet-exposed controllers rather than patch them. ReliaQuest, investigating the hotel WiFi campaign, held its assessment of the intrusion route at low-to-medium confidence and declined to name a state sponsor.
AIVD
AIVD
AIVD co-signed AA26-204A alongside CISA, the NSA and the FBI, adding its signature to the fifteen-agency coalition naming LAUNDRY BEAR. Dutch involvement continues a pattern of joint Five Eyes-adjacent advisories the agency has co-issued with CISA and NCSC through 2026.