Kronos Private Cloud, a HR management platform, has suffered a ransomware attack which puts many of its high-profile customers’ data at risk.

Ultimate Kronos Group (UKG), Kronos’ parent company, said the attack will bring down the service for “several weeks” and advised customers to “evaluate and implement alternative business continuity protocols related to the affected UKG solutions”.

UKG became aware of the attack late on Saturday, December 11, due to...