Hibiscus Petroleum said today that its IT system was “subjected to an attack” last week.
The Malaysian firm said the affected parts of the system were isolated and partially shut down.
Hibiscus said the system was gradually being restored and that production operations had not been impacted.
The company made the announcement on the Malaysian stock exchange this morning.
Hibiscus and Malaysian counterpart Ping Petroleum have a joint venture which operates the Anasuria cluster of fields in the UK North Sea.