Microsoft estimates that 8.5 million computers worldwide may be unavailable due to the global IT service outage.
This is the first time a number has been given to the event, which still causes problems worldwide.
The issue stemmed from a cybersecurity company called CrowdStrike, which sent out a compromised software update to a large number of its customers.
Microsoft, which is helping customers recover, said in a blog post that “we currently estimate that the CrowdStrike update has impacted 8.5 million Windows devices.”
That number represents less than 1% of all Windows devices worldwide, but the “broad economic and societal impact reflects the fact that many essential services are running on CrowdStrike,” according to a post by David Weston, the company’s vice president of enterprise and OS.
The company has performance telemetry data from many devices over an Internet connection, so it can determine with great accuracy how many devices are unavailable due to an outage.
The tech giant stressed that the issue was not a problem with its software, and said the incident illustrates how important it is for companies like CrowdStrike to conduct quality control checks before sending out updates.
“It also serves as a reminder of how important it is to prioritize secure deployment and disaster recovery using mechanisms that exist across the technology ecosystem,” Weston said.
The damage caused by the IT failure was enormous, and was recorded as one of the worst cyber incidents in history.
The numbers Microsoft provided would likely be the largest cyber incident ever, dwarfing all previous hacks and disruptions.
The closest thing to this was the 2017 WannaCry cyberattack, which is estimated to have affected around 300,000 computers in 150 countries. A month later, there was a similarly costly and destructive attack called NotPetya.
Meta, which operates Instagram, Facebook, and WhatsApp, also experienced a massive six-hour outage in 2021, but this was largely limited to the social media giant and a few affiliated partners.
This massive outage has prompted cybersecurity experts and organizations around the world to warn that there could be a wave of opportunistic hacking attempts related to this IT outage.
Cyber agencies in the UK and Australia have warned people to be wary of fake emails, phone calls and websites pretending to be official.
CrowdStrike CEO George Kurtz advised users to consult with the company’s official representatives before downloading the fix.
“We know that adversaries and malicious actors will seek to exploit such incidents,” he said in a blog post.
Whenever there is a major news event, especially one involving technology, hackers adapt their existing methods to account for fear and uncertainty.
According to Secureworks researchers, there has already been a surge in CrowdStrike-themed domain registrations, with hackers registering new websites that appear to be official, potentially tricking IT administrators or the public into downloading malware or providing personal information.
Cybersecurity agencies around the world are urging IT responders to seek information and assistance only through the CrowdStrike website.
This advice is primarily for IT managers trying to get their organizations back online.
However, because individuals can also be targeted, experts warn to be extremely vigilant and only take action based on information provided on official CrowdStrike channels.
