Australia's Medibank drops after ransomware attack in IT network

Reuters

Published Oct 16, 2022 06:41PM ET

Updated Oct 17, 2022 04:17PM ET

(Reuters) -Shares of Medibank Private Ltd dived nearly 5% on Monday even after the Australian health insurer assured clients that normal business operations have resumed following an attempted ransomware attack on its network.

The company, which reaffirmed that there was no evidence that customer data had been removed from the network, is on track to mark its worst day in 2-1/2 years. Shares of Medibank fell as much as 4.8% to A$3.350, their lowest level since July 19.

That was the latest in a string of cyber attacks in recent weeks to rock corporate Australia including a breach at second-largest telecoms provider Optus, which compromised data of up to 10 million customers and at a Woolworths unit that exposed data of nearly 2.2 million users.

Medibank said last Thursday it would isolate and remove access to some customer-facing systems after it detected unusual activity on its network.

The company said its investigation indicated that its cyber security systems had detected activity "consistent with the precursor to a ransomware event" but that its systems were not encrypted by ransomware.