Some of the stolen material, including financial and IT records, has already appeared on the darknet.
The K Club resort was hit by a ransomware attack just days before hosting the Irish Open.
Hackers allegedly gained access through the resort’s virtual private network and stole large volumes of data before encrypting files.
Some of the stolen material, including financial and IT records, has already appeared on the darknet.
The group, calling itself SafePay, left a ransom note on the club’s systems, according to The Sunday Times.
It typically demands payments in bitcoin, often amounting to 1–3 per cent of a company’s annual turnover.
The K Club confirmed a “cyber incident” but said no guest information was compromised.
It has notified the Data Protection Commission and introduced additional security measures.
Cybersecurity specialists believe the attackers are likely to be Russian-based.
Gardaí are aware of the incident.
The resort declined to say whether a ransom was paid.

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