What we know about global IT outage

A mass IT outage has caused chaos around the world, with major banks, media outlets and airlines among the victims.

Many flights have been grounded, with queues and delays at airports, while shops and communications have also been hit.

Cyber-security firm Crowdstrike has admitted one of its updates caused the problem, which it said affected Microsoft Windows devices.

Microsoft has said it is taking “mitigation action” to deal with “the lingering impact” of the outage.

Here is a summary of what else we know so far.

The boss of global cyber-security firm Crowdstrike, George Kurtz, has said the problems were caused by a “defect” in a “content update” for Microsoft Windows devices.

He added: “The issue has been identified, isolated and a fix has been deployed.”

Mr Kurtz said the issues did not affect other operating systems, adding: “This is not a security incident or cyber-attack.”

His statement followed widespread reports that Crowdstrike, which produces antivirus software, had issued a software update that caused Windows devices to crash.

Crowdstrike shares plunged as much as 21% in early pre-market trade. Microsoft also lost ground, as did travel and leisure stocks, as investors weighed the potential disruption for holidaymakers.

It’s a reminder of the complexity of our modern digital infrastructure that Crowdstrike, a company that’s not exactly a household name, can be at the heart of such worldwide disarray.

The US firm, based in Austin, Texas, is a listed company on the US stock exchange, featuring in both the S&P 500 and the high-tech Nasdaq indexes.

Like a lot of modern technology companies, it hasn’t been around that long. It was founded a mere 13 years ago, but has grown to employ nearly 8,500 people.

As a provider of cyber-security services, it tends to get called in to deal with the aftermath of hack attacks.

It has been involved in investigations of several high-profile cyber-attacks, such as when Sony Pictures had its computer system hacked in 2014.

But this time, because of a flawed update to its software, a firm that is normally part of the solution to IT problems is instead at their origin.

In its last earnings report, Crowdstrike declared a total of nearly 24,000 customers. That’s an indication not just of the size of the issue, but also the difficulties that could be involved in fixing it.

Each of those customers is a huge organisation in itself, so the number of individual computers affected is hard to estimate.

And according to those in the know, the fix will probably have to be applied separately to each and every device affected – causing a massive headache for IT departments everywhere.

The problem emerged in a piecemeal fashion, with first reports coming out of Australia.

Payment systems went down at Australian stores including Woolworths, while financial institutions such as the National Australia Bank were also affected.

Then the issues spread to the US. The state of Alaska warned that its emergency services were affected, while several of the country’s airlines – United, Delta and American Airlines – grounded their flights around the globe.

Australian carriers Virgin Australia and Jetstar also had to delay or cancel flights as departure screens went blank at Sydney airport.

Tokyo-Narita and Delhi airports said services had been affected. European airports reported that the outage was causing delays, with long queues reported at London’s Stansted and Gatwick and Amsterdam’s Schiphol.

Ryanair said it was experiencing “potential disruptions across the network”, which it said were due to a third-party outage.

Broadcasters were also caught up in the chaos, including Sky News in the UK, which spent several hours off air.

As the full extent of the disruption became clear, more firms and institutions started reporting problems.

The London Stock Exchange said it was working as normal, but there were issues with its news service, used by companies to report market-sensitive information in a timely way.

Israel says 15 hospitals have switched to manual processes but this has not affected medical treatment. Ambulances are being told to take new cases to other hospitals.

And Poland’s largest container terminal, the Baltic Hub in the northern city of Gdansk, has said the outage is “hampering terminal operations” and has asked companies not to send containers to the port.

In the UK, railway companies have reported delays and said they were experiencing “widespread IT issues”, while some doctors’ surgeries in England reported issues with booking appointments.

The problems have extended to upmarket UK bakery chain Gail’s, which has said it is currently unable to take in-store payments.