An increase in “sophisticated, high-impact” ransomware incidents is posing a growing threat to critical infrastructure organisations, western government agencies warn.

The UK’s National Cyber Security Centre (NCSC), the US Cybersecurity and Infrastructure Security Agency (CISA), and the Australian Cyber Security Centre published a joint advisory (PDF) on Wednesday that highlighted the evolution of techniques deployed by cybercriminals and the growing maturity of the ransomware-as-a-service business model.