Why have Medibank shares just been suspended from trading on the ASX?

The company's stock could remain suspended until Wednesday.

Key points
  • The Medibank share price has been suspended as the company deals with the fallout of a cyberattack 
  • The stock will remain on ice until Wednesday unless the company provides an update on the incident
  • Medibank confirmed hackers were threatening to release the personal data of customers, including some medical information, yesterday

The Medibank Private Ltd (ASX: MPL) share price has been suspended this morning after the health insurer confirmed hackers are holding the company to ransom.

The cybercriminal is threatening to release the personal data, including medical and possibly credit card information, of the company's customers.

The company will return to trade on the release of a further announcement or Wednesday's open, whichever comes soonest.

Let's take a closer look at what's going on with the S&P/ASX 200 Index (ASX: XJO) health insurer.

woman putting her hand up to stop sitting in white office

Image source: Getty Images

Medibank shares suspended amid cyberattack fallout

The Medibank share price is back on ice amid what originally appeared to be a relatively banal "cyber incident".

However, as the week has unfolded, the seriousness of the attack has come to light.

Medibank CEO David Koczkar has written to customers informing them a cybercriminal has been confirmed to have stolen data from the company's ahm and international student systems.

The data includes names, addresses and phone numbers, dates of birth, Medicare numbers, and some claims data. Such claims data include codes related to a person's diagnosis and procedures.

The company is so far unable to confirm claims the hacker has also taken information relating to credit card security.

Koczkar "unreservedly" apologised to customers for the incident, saying:

Our teams are continuing to work around the clock to understand what additional customer data has been affected, and how this will impact them. We expect the number of affected customers to grow as the incident continues.

In requesting today's suspension, the company said:

Whilst there is currently no further information to provide to the market … Medibank is seeking voluntary suspension of its shares to enable it to manage its continuous disclosure and provide an update to the market on the status and implications of the cyber incident.

The Office of the Australian Information Commissioner (OAIC) has also confirmed it's making inquiries with Medibank following the breach.

Australian information commissioner and privacy commissioner Angelene Falk said the attack is "of great concern, given the sensitive information that may be involved".

Medibank shares traded for three days this week, falling 0.3% in that time to $3.51. The shares were placed in a trading halt on Wednesday afternoon before being suspended today.

Motley Fool contributor Brooke Cooper has no position in any of the stocks mentioned. The Motley Fool Australia's parent company Motley Fool Holdings Inc. has no position in any of the stocks mentioned. The Motley Fool Australia has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy. This article contains general investment advice only (under AFSL 400691). Authorised by Scott Phillips.

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