Microsoft says cyber-attack triggered latest outage

The Microsoft logo outside a building at nightImage source, Reuters
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A global outage affecting Microsoft products including email service Outlook and video game Minecraft has been resolved, the technology giant said in an update, external.

The firm said preliminary investigations show the outage was caused by a cyber-attack and a failure to properly defend against it.

Earlier, the company issued an apology for the incident, which lasted almost 10 hours and caused thousands of users to report issues with Microsoft services.

It comes less than two weeks after a major global outage left around 8.5 million computers using Microsoft systems inaccessible, impacting healthcare and travel, after a flawed software update by cybersecurity firm CrowdStrike.

"While the initial trigger event was a Distributed Denial-of-Service (DDoS) attack... initial investigations suggest that an error in the implementation of our defences amplified the impact of the attack rather than mitigating it," said an update on the website of the Microsoft Azure cloud computing platform.

DDoS attacks work by flooding a website or online service with internet traffic in an attempt to throw it offline, or otherwise make it inaccessible.

"It seems slightly surreal that we’re experiencing another serious outage of online services from Microsoft," said computer security expert Professor Alan Woodward.

“You’d expect Microsoft’s network infrastructure to be bomb-proof."

Earlier, an alert on the technology giant's service status website , externalsaid the outage affected Microsoft Azure - the cloud computing platform behind many of its services - and Microsoft 365, which includes systems like Microsoft Office and Outlook.

It also listed its cloud systems Intune and Entra as among those impacted.

Microsoft said it had implemented a fix for the problem which "shows improvement", and it would monitor the situation "to ensure full recovery", external.

"We sincerely apologise for the inconvenience," it said in a post on X, formerly Twitter, external.

Who has been affected?

The outage appears to have impacted other services which rely on Microsoft's platforms, with Cambridge Water among those affected.

"Due to worldwide issues with Microsoft Azure, a problem with our website is affecting several services including MyAccount and PayNow," it said in a post on X, external.

The HM Courts and Tribunals Service - which is responsible for the administration of criminal, civil and family courts and tribunals in England and Wales - said it was aware of issues with "multiple online services", external.

Some customers of NatWest also reported issues.

A spokesperson for the bank told the BBC: “We are aware that some customers experienced difficulties accessing our webpages today. This was linked to the issues reported by Microsoft Azure which has affected some Microsoft services globally.

“The issue has now been resolved and our webpages are functioning as normal. We apologise to customers for any inconvenience caused.”

Meanwhile, top flight Dutch football team FC Twente tweeted an update to their fans, external to say its ticketing website and club app were unavailable to supporters as a result of the outage.

The issues with one of Microsoft's premier products appeared hours before the tech giant was due to provide its latest financial update.

Microsoft Azure has been a key profit driver for Microsoft in recent years.

But demand has slowed in recent months, rattling investors.

Shares in the firm dropped by 2.7% in after-hours trade on Tuesday after the company reported weaker growth than expected in the April-June period.

Revenue in the "intelligent cloud" unit rose 21% year-on-year in the quarter, Microsoft said.

Overall revenue increased 15% to $64.7bn (£50.4bn), while profit rose 11% to $22bn.

Additional reporting by Natalie Sherman, Chris Vallance and Liv McMahon