CrowdStrike is actively working with customers impacted by a defect found in a single content update for Windows hosts. Mac and Linux hosts are not impacted. This is not a security incident or cyberattack. The issue has been identified, isolated and a fix has been deployed. We refer customers to the support portal for the latest updates and will continue to provide complete and continuous updates on our website. We further recommend organizations ensure they’re communicating with CrowdStrike representatives through official channels. Our team is fully mobilized to ensure the security and stability of CrowdStrike customers.
Banks, airports, TV stations, health care organizations, hotels, and countless other businesses are all facing widespread IT outages, leaving flights grounded and causing widespread disruption, after Windows machines have displayed errors worldwide.
In the early hours of Friday, companies in Australia running Microsoft’s Windows operating system started reporting devices showing Blue Screens of Death (BSODs). Shortly after, reports of disruptions started flooding in from around the world, including from the UK, India, Germany, the Netherlands, and the US: TV station Sky News went offline, and US airlines United, Delta, and American Airlines issued a “global ground stop” on all flights.
Engineers from CrowdStrike posted to the company’s Reddit forum that it has seen “widespread reports of BSODs on Windows hosts” occurring across its software, is working on the problem, and has advised a workaround for impacted systems. It also issued instructions to its customers in an advisory.
Microsoft said it is aware of the issue affecting machines running Windows, and noted it is affecting systems running CrowdStrike’s Falcon security software.
The outage has been blamed on a software update by cybersecurity firm CrowdStrike, which has resulted in many Windows systems experiencing the dreaded “Blue Screen of Death” (BSOD) while booting.
The underlying issue causing outages for Microsoft’s 365 apps and services—including Outlook, Teams and Office—has been fixed, the company said, though a “residual impact” is continuing to affect some services.
CrowdStrike President and chief executive George Kurtz said the company was “actively working” with customers impacted by an issue found in a content update on Windows computers, adding the “issue has been identified, isolated and a fix has been deployed.”
The U.S. Emergency Alerts System said 911 lines in multiple states were down.
According to the Federal Aviation Administration, nearly all major American carriers—including Delta, American and United—have been forced to temporarily ground all their flights due to the outage, while carriers and airports including Air India, KLM, Hong Kong International Airport, Berlin Brandenburg Airport and London Stansted also reported disruptions, forcing some of them to rely on manual check-ins with long queues being reported.
The London Stock Exchange group said its workspace platform was also facing an outage preventing it from publishing statements while banks and payment terminals in Australia were also affected, though the New York Stock Exchange reportedly said its systems were unaffected.
Office 365 Resolved. Previously:
Title: Users may be unable to access various Microsoft 365 apps and services
User impact: Users may be unable to access various Microsoft 365 apps and services.
More info: Impact included but was not limited to the following apps and services:
- OneDrive for Consumer: Users may have been unable to access OneDrive for Business content.
- OneNote: Users may have been unable to sync content, experienced delays syncing notebooks, or may have been unable to open notebooks.
Final status: We've confirmed that impact has been resolved following our mitigation efforts.
Start time: Thursday, July 18, 2024, at 10:59 PM UTC
End time: Friday, July 19, 2024, at 4:21 AM UTC
Title: Users may be unable to access various Microsoft 365 apps and services
User impact: Users may be unable to access various Microsoft 365 apps and services.
More info: Impact includes but is not limited to the following apps and services:
- OneDrive for Consumer: Users may be unable to access OneDrive for Business content.
- OneNote: Users may be unable to sync content, have delays syncing notebooks, or may be unable to open notebooks.
Current status: We still expect that users will continue to see gradual relief as we continue to mitigate the issue. The latest information on impacted and recovered services will be provided within the "More info" section of this communication. Additionally, we are shifting our focus to developing a mitigation that will help determine and resolve the underlying source of the problem.
Next update by: Friday, July 19, 2024, by 5:30 AM UTC
Title: Users may be unable to access various Microsoft 365 apps and services
User impact: Users may be unable to access various Microsoft 365 apps and services.
More info: Impact includes but is not limited to the following apps and services:
- OneDrive for Consumer: Users may be unable to access OneDrive for Business content.
- OneNote: Users may be unable to sync content, have delays syncing notebooks, or may be unable to open notebooks.
Current status: We're continuing to notice service health improvements and users will gradually see relief as our efforts progress. Concurrently, we're still developing a fix to address the underlying issue of this incident. We appreciate your organization's patience and understanding while we resolve this event.
Next update by: Friday, July 19, 2024, by 4:30 AM UTC
Title: Users may be unable to access various Microsoft 365 apps and services
User impact: Users may be unable to access various Microsoft 365 apps and services.
More info: Impact includes but is not limited to the following apps and services:
- OneDrive for Consumer: Users may be unable to access OneDrive for Business content.
- OneNote: Users may be unable to sync content, have delays syncing notebooks, or may be unable to open notebooks.
Current status: We’re still observing a positive trend of service availability as our mitigation efforts progress. In parallel, we are working on a mitigation to address the suspected root cause of this event. We remain committed to treating this incident with the highest priority to ensure it resolves in a timely manner.
Next update by: Friday, July 19, 2024, by 3:30 AM UTC
Title: Users may be unable to access various Microsoft 365 apps and services
User impact: Users may be unable to access various Microsoft 365 apps and services.
More info: Impact includes but is not limited to the following apps and services:
- OneDrive for Consumer: Users may be unable to access OneDrive for Business content.
- OneNote: Users may be unable to sync content, have delays syncing notebooks, or may be unable to open notebooks.
Current status: Our internal telemetry and customer signals indicate that service availability is gradually returning to a healthy state following our traffic redirection efforts. We have also identified a potential root cause that may have contributed to the impact. Our team is currently validating these findings and our mitigation strategy to ensure the issue is resolved as quickly as possible.
Next update by: Friday, July 19, 2024, by 2:30 AM UTC
Title: Users may be unable to access various Microsoft 365 apps and services
User impact: Users may be unable to access various Microsoft 365 apps and services.
More info: Impact includes but is not limited to the following apps and services:
- OneDrive for Consumer: Users may be unable to access OneDrive for Business content.
- OneNote: Users may be unable to sync content, have delays syncing notebooks, or may be unable to open notebooks.
Current status: We remain focused on redirecting the impacted traffic to healthy systems as we investigate the root cause. Your organization may experience relief as our mitigation efforts progress. We understand the impact that this issue may have on your organization and we're continuing to treat this event with the highest priority.
Next update by: Friday, July 19, 2024, by 1:30 AM UTC
Title: Users may be unable to access various Microsoft 365 apps and services
User impact: Users may be unable to access various Microsoft 365 apps and services.
More info: Impact includes but is not limited to the following apps and services:
- OneDrive for Consumer: Users may be unable to access OneDrive for Business content.
Current status: We're rerouting affected traffic out of the impacted infrastructure while we continue to investigate the cause of the issue.
Next update by: Friday, July 19, 2024, by 12:30 AM UTC
