CNBC's live blog covering the IT outage impacting businesses worldwide is now closed.

Businesses worldwide grappled with an ongoing major IT outage Friday, as financial services and doctors' offices were disrupted, while some TV broadcasters went offline. Air travel has been hit particularly hard, with planes grounded, services delayed and airports issuing advice to passengers.

The outage came as cybersecurity giant CrowdStrike experienced a major disruption early Friday following an issue with a recent tech update.

CrowdStrike CEO George Kurtz has since said that the company is "actively working with customers impacted by a defect found in a single content update for Windows hosts," stressing that Mac and Linux hosts are not affected.

"This is not a security incident or cyberattack. The issue has been identified, isolated and a fix has been deployed," he said on social media.

One expert suggested it may be the "largest IT outage in history."

Separately, Microsoft cloud services were restored after an outage, the company said on Friday, even as many users continued to report issues.

Shares of CrowdStrike closed down 11%.

Read more:

• How a software update from cyber firm CrowdStrike caused one of the world’s biggest IT blackouts
• Flights grounded, passengers to see delays amid global IT outage
• CrowdStrike shares fall after major outage hits businesses worldwide
• Microsoft, CrowdStrike IT outage hits global supply chain, with air freight facing days or weeks to recover
• Global tech outage hits financial services companies, including Charles Schwab

FTC Chair Lina Khan connects outage to competition and 'fragile systems'

FTC Chair Lina Khan weighed in on the ongoing CrowdStrike outage in a series of posts on X on Friday. Without mentioning CrowdStrike or Microsoft, she appeared to blame the outage on concentrated market power, which creates "fragile systems," she wrote.

"Concentrating production can concentrate risk, so that a single natural disaster or disruption has cascading effects," Khan wrote in the series of posts.

Khan did not announce an FTC investigation of the incident, but she linked to unrelated past actions she has taken, including opening up a query on cloud computing companies, and seeking public comment on companies that frequently buy smaller competitors, like in the technology industry.

— Kif Leswing

Amazon warehouses and internal software disrupted by outage

Some Amazon warehouses in the U.S. were grappling with disruptions set off by the global IT outage.

Three Amazon warehouse staffers said the outage took down an app used by employees to manage their schedules and submit time off requests, called A to Z, early Friday morning, though it has since been restored in some areas. The employees asked to remain anonymous because they weren't authorized to speak publicly about the situation.

The outage also disrupted some Amazon employees' ability to access an internal service called "Anytime Pay," which allows staffers to withdraw earnings before their next paycheck. "Anytime Pay is unavailable due to a global outage impacting users to access internal IT services," according to a notice on Amazon's internal payroll site for warehouse staffers, which was viewed by CNBC.

At some sites, operations were briefly halted. An Amazon warehouse worker in South Carolina, who asked to remain anonymous, said their site passed the time by performing karaoke in exchange for "cola cash," or credits that can be used to purchase snacks and drinks at the facility.

The disruptions also touched Amazon's trucking operations. Truck drivers who use Relay, a platform that lets them book jobs moving Amazon cargo, said they were briefly unable to pick up loads at Amazon warehouses due to system issues.

"Everything was bluescreened," said Dwight Evitt, a truck driver in San Marcos, Texas.

Representatives from Amazon didn't respond to requests for comment.

— Annie Palmer

CrowdStrike CEO George Kurtz apologizes for global outage in blog post

CrowdStrike CEO George Kurtz apologized in a blog post for the global outage Friday and reiterated that his company is working closely with impacted customers and partners to restore all systems.

Kurtz encouraged customers to "remain vigilant" in ensuring they engage with official CrowdStrike representatives as they seek support.

"We know that adversaries and bad actors will try to exploit events like this," he wrote.

He added that the company's blog and technical support portal will remain the official channels for updates.

Kurtz reiterated the outage was caused by a defect in a Falcon content update for Windows hosts, and Mac and Linux hosts were not impacted. He emphasized again that the outage was not caused by a security breach or cyberattack.

"As we resolve this incident, you have my commitment to provide full transparency on how this occurred and steps we're taking to prevent anything like this from happening again," he wrote.

-- Katie Bartlett

Railroad Union Pacific returns to full capacity

Railroad Union Pacific is now back to full capacity after facing processing delays and "varying levels of impact" earlier Friday.

"The vast majority of our customers' freight is moving and full fluidity is returning to our network after this morning's CrowdStrike software outage," Union Pacific told CNBC. "In response to the outage our teams swiftly implemented protocols and communication plans, which allowed us to safely keep our trains running."

-- Ece Yildirim

CommonSpirit Health bringing computers back online one by one, CIO says

At CommonSpirit Health, which provides care across 150 hospitals in 24 states, employees noticed that many of the health systems' desktop computers were displaying a blue error screen in the early hours of Friday morning.

The health system has tens of thousands of computers, and they serve as a "window" into all of the organization's other systems, Daniel Barchi, CIO at CommonSpirit, told CNBC.

"It's the way our physicians who are doing surgery have access to the images that have been made on a patient's MRI," Barchi said. "It's the way the nurse knows which drugs to give to the patient."

Barchi said the disruption was deemed a "priority one event," and that he and other senior IT leaders began working to identify the issue around 2 a.m. They determined the problem was related to an update that CrowdStrike had pushed out, and they were able to contain it before it had finished rolling out to all the computers within CommonSpirit.

But though some computers remained operational, the compromised computers must be fixed manually, one by one.

"We were all stunned by the fact that if a computer gets this blue screen lock up, there's no way to push a software patch to fix it," he said. "You literally have to go up to it, login as an administrator, a technology person, and then delete a line of code and make that enabled to come back online."

Barchi said CommonSpirit has managed to bring many of its computers back online, and many hospitals are returning to business as usual. The health system will continue its remediation process and work to fix its servers through the rest of the day, he said.

-- Ashley Capoot

Tesla temporarily halts production at some manufacturing facilities after outage

Electric vehicle maker Tesla temporarily halted production on lines at some of its manufacturing facilities on Friday after an unprecedented IT outage impacted global operations due to system issues at cybersecurity firm CrowdStrike.

According to correspondence obtained by CNBC, Tesla's IT teams notified employees that there was a "windows host outage," and different systems were affected including "servers, laptops and manufacturing devices." The IT teams informed Tesla employees that they may see a "blue screen" on their various devices.

Tesla CEO Elon Musk, who also owns social media platform X, posted several complaints about the CrowdStrike outages to his account, which has more than 190 million followers, throughout the morning.

Two Tesla employees who spoke with CNBC, but asked to remain unnamed because they were not authorized to speak on behalf of the company, said that some manufacturing lines were slow to start on Friday morning, and others were temporarily halted in California and Nevada. They also said managers were telling some workers to prepare for canceled shifts or to go home early.

Business Insider, which first reported on the IT memo, wrote that workers in Tesla's Texas vehicle assembly plant were sent home overnight in response to the outages as well.

As a key Tesla vendor, Microsoft, scrambled to restore its apps and services Friday morning, CEO Satya Nadella wrote in a statement on X that an update from CrowdStrike on Thursday impacted global IT systems.

In replies to Nadella on X, Musk wrote that the outages had caused a "seizure" to the automotive supply chain, adding, "We just deleted CrowdStrike from all our systems, so no rollouts at all."

Employees confirmed that Tesla was using CrowdStrike as of Friday.

Tesla shares were down more than 3% in afternoon trading on Friday. Tesla did not immediately respond to a request for further information.

— Lora Kolodny

Outage hits Starbucks mobile ordering, causing chaos at stores

The outage has also halted the ability to order Starbucks through its mobile app.

The issue has caused chaos for baristas and other Starbucks employees, leading to temporary store closures and frantic posts online seeking assistance.

At some stores, employees created various handwritten signs for customers, announcing store closures or asking customers to walk up or show an employee a mobile receipt.

Read the full story here.

— Kat Tenbarge, NBC News

More than 4,000 flights cancelled globally due to outage, data shows

Nearly 4% of all scheduled flights around the world have been cancelled due to the disruption, according to new data from the aviation analytics firm Cirium on Friday. The firm said 4,295 flights had been cancelled as of 12 p.m. ET.

In the U.K., 4.6% of all scheduled departures, or 143 flights, have been cancelled, according to Cirium. Around 140 inbound arrivals have also been cancelled.

-- Ashley Capoot

Timelapse shows how air traffic over the U.S. was impacted by global IT outage

Video from flight tracker Flightradar24 shows how passenger flights over the U.S. were affected during the early morning hours after a global IT outage hit airlines and airport services nationwide.

— Gabriel Cortes, Riya Bhattacharjee

Microsoft CEO says company working closely with CrowdStrike

Microsoft CEO Satya Nadella said that the company was working with CrowdStrike to address the global outage.

"We are aware of this issue and are working closely with CrowdStrike and across the industry to provide customers technical guidance and support to safely bring their systems back online," Nadella said in a post on X.

CrowdStrike and Microsoft have had an adversarial relationship, since CrowdStrike does a brisk business pitching clients on its ability to address vulnerabilities in Microsoft's systems. CEO George Kurtz roundly criticized Microsoft in an interview with CNBC last year.

-- Rohan Goswami

Tired travelers cope ... and drink

Travelers stuck this morning at JFK Airport in New York met the delays with resignation, weariness and a need to hit the bar.

Colby Black, 45, took the delays in stride, even though he wasn't sure when his rescheduled flight to Los Angeles would take off. It was originally set to depart at 6 a.m. 

"I'm just tired. I want to sleep," said Black, who woke up at 3 a.m. "But otherwise, yeah, it happens."

One mother said she hadn't slept the night before, just so she and her infant son could get to JFK on time.

"I'm still up, running on no sleep," she said as she was seated on a barstool beside a heavy pour of chilled white wine. She wasn't originally planning to order a preflight drink.

"Hell no. I got to the airport at 4 o'clock this morning," she said.

-- Kevin Breuninger

U.S. securities regulators are monitoring the situation, as impacted stocks pare back losses.

The Securities and Exchange Commission said it isn't impacted by the outage but is "monitoring for market-related impacts."

CrowdStrike shares are down around 9% in midday trading, significantly paring back earlier losses. It traded down as much as 20% in pre-market trading. Microsoft shares are flat for the day.

Shares in United Airlines and American Airlines, both of which issued ground stop orders earlier today, have recovered earlier losses as well.

- Rohan Goswami

CrowdStrike headed for worst week since November 2022

CrowdStrike's major IT outage, which has affected businesses globally, is leading the stock to its worst weekly performance since November 2022.

Shares were 9% lower Friday, pulling the stock down by nearly 16% week to date.

CrowdStrike shares are still higher by 22.5% in 2024.

— Hakyung Kim

Drugmaker Amgen is working to recover impacted systems

Drugmaker Amgen, a CrowdStrike customer, said Friday it is assessing the impact of the global outage and working to recover affected systems "as quickly as possible." 

Amgen did not disclose what kind of systems were impacted.

In a statement on its website, the California-based company urged employees with impacted devices to only follow its guidance. -- Annika Kim Constantino

Epic Systems says outage is preventing some health organizations from accessing some patient records

The health-care software vendor Epic Systems, which houses more than 305 million patient medical records, said the outage has caused technical issues that are preventing some health-care organizations from using its systems. 

An Epic spokesperson said the disruption is not affecting the company's services directly, but it has received reports that the laptop and desktop workstations that some groups use to access Epic are down. Additionally, some groups have reported problems with their data center software, which means they are unable to access patient records through Epic.

"Organizations that have been affected are following pre-established downtime protocols to continue delivering patient care," an Epic spokesperson told CNBC in a statement. "Epic staff are working with customer IT teams to restore access as fixes or mitigation approaches are available from CrowdStrike."

Epic said its platform for cloud-based applications called Nebula was impacted by the outage. Features like its telehealth offering were temporarily unavailable, but Epic said access has been restored. Epic is continuing to monitor Nebula, the company added. 

-- Ashley Capoot

United ground stop lifted for all flights

United Airlines' ground stop has been lifted for all airports, according to an Air Traffic Control System Command Center advisory.

Earlier Friday, the airline had resumed some flights but told CNBC it expected "schedule disruptions to continue throughout Friday."

— Ece Yildirim

England's National Health Service says majority of general practitioners disrupted

England's National Health Service on Friday said the global outage has impacted its system for booking doctors' appointments and managing patient records, which is disrupting the majority of general practitioner practices.

That appointment and records system, known as EMIS, is used by nearly 60% of England's general practitioner practices, which provide medical services to patients of all ages.

NHS, a publicly funded healthcare system, is also experiencing issues with some administrative systems in hospitals, a spokesperson said in a statement. Staff is working manually from paper as a result, but "care is continuing as normal" in the majority of hospitals, they added.

"The NHS has long standing measures in place to manage the disruption, including using paper patient records and handwritten prescriptions, and the usual phone systems to contact your" general practitioner, the spokesperson said.

Emergency services are currently not affected, according to the spokesperson.

- Annika Kim Constantino

Sec. Buttigieg expects transportation delays to be 'resembling normal' by Saturday

Secretary of Transportation Pete Buttigieg said Friday on CNBC's "Squawk on the Street" that he expects the transportation delays to be smoothed out and "resembling normal" by Saturday.

"The issue has been identified. It's really a matter of the kind of ripple or cascade effects as they get everything in their networks back to normal," Buttigieg said. "These flights, they run so tightly, so back-to-back that even after a root cause is addressed, you can still be feeling those impacts throughout the day."

Buttigieg added that there is no indication on any impact to the Department of Transportation's own systems including air control, but that he is expecting more issues on the airlines' side.

"We're tracking all of the various impacts hitting different forms of transportation. The one that I think most people are likely to experience directly is those airline cancellations and delays if you're planning to fly today," Buttigieg said.

Nearly 28,000 flights had been delayed globally as of about 11 a.m. ET Friday, with roughly 4,700 of those delays within, into or out of the United States, according to FlightAware data. More than 2,950 flights have been cancelled, with almost 1,800 of them U.S. flights.

— Ece Yildirim

CrowdStrike CEO apologizes, says that outage is not related to cybersecurity

CrowdStrike CEO George Kurtz wrote in a post on X that Friday's incident was not related to cybersecurity and that the issue — related to a Falcon content update for Windows Hosts — was identified earlier, with a solution deployed. He added that customers "remain fully protected."

"We understand the gravity of the situation and are deeply sorry for the inconvenience and disruption," Kurtz wrote. "We are working with all impacted customers to ensure that systems are back up and they can deliver the services their customers are counting on."

— Hayden Field

Federal Reserve says critical systems are 'operating normally'

The Federal Reserve said its systems are working amid the global tech outage.

"Critical Federal Reserve Systems are operating normally. We are monitoring the situation and working closely with industry and other government agencies to assess the situation," the central bank said in a statement to CNBC.

— Leslie Picker

Charles Schwab says some online features can be 'intermittently slow or unavailable' after outage

Charles Schwab, which operates trading services including Think or Swim, said in a Friday X post that "certain online functionality may be intermittently slow or unavailable."

"Please do not place trades twice, as duplicate trades may be created," Charles Schwab said in a message sent to account holders through the Charles Schwab app. "We're actively working with the vendor to resolve the issue. Phone services may be disrupted and hold times may be longer than usual."

Vanguard and Fidelity were not impacted by outages.

"After the widespread third-party outage, Vanguard's portfolio management trading functions across all regions are operating as normal and there is no current impact to our products or pricing," a Vanguard spokesperson said, noting they will continue to "monitor the situation."

Fidelity told CNBC they are aware of the issues and the company did not appear to be impacted as of mid-day Friday.

-- Jordan Novet and Kate Dore

Union Pacific facing processing delays, other railroads operating normally

Railroad Union Pacific is seeing "varying levels of impact" across its network, the company told CNBC in a statement, with back-up protocols enabling communication between teams and dispatchers.

"We are doing everything possible to keep freight moving, but there have been some processing delays in customer shipments as we address targeted areas impacted on our network," Union Pacific said.

Other major railroad companies Norfolk Southern, BNSF and CSX told CNBC they were unaffected. A BNSF representative told CNBC that it will continue to monitor the situation for potential impacts.

— Ece Yildirim and Lori Ann LaRocco

FedEx says 'substantial disruptions' from outage, UPS also impacted

FedEx said it's experiencing "substantial disruptions" due to the global tech outage. UPS is also reporting an impact, according to statements from the companies.

FedEx said that there could be delays for package deliveries that were expected to arrive Friday, but the shipping company is attempting to mitigate impacts. The company has activated contingency plans to address the disruption throughout its networks, according to the statement.

UPS also said there may be service delays, as it works to resolve all issues. The software outage is impacting some UPS computer systems in the U.S. and Europe, but the company's airline and driver delivery systems are still operating effectively, according to the statement.

DHL, for its part, said in a statement the outage currently had "only very limited and local impact." DHL also said that some suppliers and business partners are affected, and that it's monitoring the situation.

— Justine Fisher

Amazon Web Services says some 'connectivity issues' caused by CrowdStrike glitch

Amazon's cloud computing service alerted its customers to some "connectivity issues and reboots" that may be experienced as a result of the CrowdStrike outage.

AWS services "continue to operate normally," but some "Windows Instances, Windows Workspaces and Appstream Applications" that use CrowdStrike encountered issues early Friday morning, according to a notice on AWS' service dashboard.

The company provided users with a number of recovery options to bring their applications back online, including to "delete the CrowdStrike Falcon agent file on the affected" instance, or server.

— Annie Palmer

President Biden briefed on outage, in touch with CrowdStrike and affected entities

President Biden has been briefed on the global outage, and the administration is in touch with both CrowdStrike and impacted entities, according to a White House official.

"His team is engaged across the interagency to get sector by sector updates throughout the day and is standing by to provide assistance as needed," the official said.

— Hayden Field

DHS working with CrowdStrike, others to ‘assess and address’ outage

The Department of Homeland Security says it's working with CrowdStrike, Microsoft and government agencies to evaluate the outage. 

"The Department, and the Cybersecurity and Infrastructure Security Agency (@CISAgov) are working with CrowdStrike, Microsoft and our federal, state, local and critical infrastructure partners to fully assess and address system outages," the department said in a post on X.

— Sean Conlon

Health systems across the U.S. facing outages

The Mount Sinai Health System in New York City said Friday that it has "identified and isolated" systems that have been affected by the disruption. The health system is made up of eight hospital campuses and the Icahn School of Medicine at Mount Sinai. The organization's technology team is actively working to restore impacted systems, it said.

"Patient safety remains our top priority and we will provide updates as the situation evolves," Mount Sinai said in a statement to CNBC. "We are thankful to our staff who are working to ensure care continues with minimal interruption."

The University of Miami Health System, which operates several hospitals in South Florida, on Friday said it is experiencing "connectivity issues across various applications," including its electronic medical record system. The global outage did not compromise its data security and confidentiality, the health system said in a Facebook post. 

All University of Miami hospitals and clinics will remain open, but patients should expect delays until systems are fully restored, according to the post. Impacted facilities are using paper orders to distribute information.

The University of Miami's information technology team "is actively working to resolve the disruption and bring all systems back online," the post added. 

UVA Health, a health system associated with the University of Virginia in Charlottesville, said in a statement Friday that it is operating on a "modified schedule" due to the global outage. Most ambulatory clinics will be closed.

Other clinics are also closed as of Friday morning but may reopen, according to the UVA website.

UVA Health operates an academic medical center, three community hospitals, a specialty rehabilitation hospital and primary and specialty care clinics throughout Virginia.

Penn Medicine in Pennsylvania said it may have to cancel and reschedule appointments in some locations because of the outage, according to an alert on its website. The health system said its hospitals are staffed and continuing to provide care to patients.

"We are making every effort to contact patients whose appointments need to be canceled," Penn Medicine said.

The Cleveland Clinic in Ohio told CNBC that patient care is not affected by the outage, but some of its tech has been impacted. The health system said it is continuing to provide care at all locations.

CommonSpirit Health, which provides care across more than 2,200 sites in 24 states, said some of its facilities have been impacted by the disruption. The health system said patients will be contacted directly if their appointments are affected.

"We continue to provide safe, high-quality care to our patients and thank everyone for their patience as our teams take immediate action to restore any impacted systems," CommonSpirit told CNBC in an interview.

- Annika Kim Constantino, Ashley Capoot

Crowdstrike CEO: Working with 'every' customer

Crowdstrike CEO George Kurtz said that the company was working aggressively with every customer to fix outages, but said that because of idiosyncrasies with each corporate network, the repair speed would vary.

"We're working individually with each and every customer to make sure we can get them up and running," Kurtz said on CNBC's "Squawk on the Street."

Kurtz sidestepped a question about the legal risk to the company should customers opt to sue. Kurtz noted that he has been in cybersecurity "for a long time" and that CrowdStrike has a strong reputation and level of trust with customers.

-- Rohan Goswami

U.S. markets operating normally

New York Stock Exchange and Nasdaq officials said the exchanges are up and running Friday.

"NYSE markets are fully operational and we expect a normal open this morning," a spokesperson for the exchange said Friday.

The Nasdaq said its European markets and US pre-market are operating normally. "We expect our US markets to open normally," the firm said.

-- Jeff Cox

Passengers face flight delays

Passengers at New York's John F. Kennedy International Airport faced flight delays as part of the major worldwide IT outage.

Several airlines had requested assistance early Friday with ground stops for their fleets until issues were resolved, the Federal Aviation Administration said.

American Airlines, Delta Air Lines and United Airlines said they were resuming some flights. But they warned of delays, and both Delta and United issued waivers to allow customers to change their travel plans.

Read the full story here.

— Kevin Breuninger and Michele Luhn

Two South African banks say services fully restored

Two South African lenders said they have wholly resumed services that were temporarily affected by the ongoing global cyber outage.

"Phew! That was rough, but all of our services are now back up and running," retail bank Capitec said in a social media update, after alerting customers it was experiencing "nationwide service disruptions" earlier in the day because of "an unexpected issue with an international service provider."

Its card payments and ATM were not impacted at the time.

Absa Group also said that "the technical matter relating to the global outage has been resolved" with respect to its own services, after flagging difficulties a few hours prior.

"Absa's digital banking channels, point-of-sale services and ATMs are all functional and available for you to continue banking," it noted on social media platform X.

— Ruxandra Iordache

Mass General Brigham cancels non-urgent surgeries, hospital visits

Mass General Brigham is canceling all previously scheduled non-urgent surgeries, procedures and medical visits on Friday "due to the severity" of the global IT outage, the integrated healthcare system said in a post on X.

It added that its clinics and emergency departments are still open for urgent health concerns and patients already receiving care. The system has "dedicated every available resource to resolve this issue as quickly as possible, and we apologize for the inconvenience this has caused our patients." 

Mass General Brigham operates two of the U.S.'s top-ranked hospitals, Massachusetts General Hospital and Brigham and Women's Hospital in Boston, along with several other clinics and labs.

-- Annika Kim Constantino

MTA says New York City's transit system is operating normally

The MTA said that train and bus service was unaffected by the outage, but that some customer-facing systems were down and that passengers should follow instructions from crew and in the station.

- Rohan Goswami

CrowdStrike CEO: ‘We’re deeply sorry’

CrowdStrike CEO George Kurtz apologised Friday for the systems update that caused a global IT outage, telling NBC "we're deeply sorry."

Businesses are still reeling, with many flights grounded and payments systems downed after the cybersecurity giant's antivirus software update went awry.

"The system was sent an update, and that update had a software bug in it and caused an issue with the Microsoft operating system," he told NBC's "Today".

The CEO reiterated that it was not a security incident or cyberattack, and that the company is working with customers to get them back online.

He said the update was normal and part of the firm's routine process to prevent security risks. However, he noted that a thorough investigation would need to be carried out into what went wrong.

"We have to go back and see what happened here. But if there's a negative interaction with the way some of these operating systems work — in this particular case, it was, it was only a Microsoft operating system that was impacted — you'll see a reaction like this," he said.

- Karen Gilchrest

British hospital declares critical incident in the wake of IT outage

Britain's Royal Surrey Hospital in Guildford has declared a "critical incident" due to external IT issues that are affecting its services, as well as Varian — the IT system that it deploys for radiotherapy treatments.

A critical incident can be declared when hospitals and staff face extraordinary pressures.

The institution said that it is now able to deliver radiotherapy services, but it has had to reschedule appointments due to take place this morning. The disruptions may affect appointments into next week, Royal Surrey noted.

— Ruxandra Iordache

UK retailers impacted by IT outage

Several major U.K. companies were also impacted by Friday's IT outage, with food retailer Waitrose temporarily halting contactless payments.

The British grocer said in a statement that all payment methods had resumed following a brief suspension, and that its John Lewis stores had not been impacted.

Other stores such as the Co-op appeared to resort to cash-only payments as the outage impacted self-checkout and cashier payment systems, according to posts shared on social media platform X.

Photos showed supermarket shelves with "cash-only" signs, while another post suggested bakery chain Gail's was not taking card payments. Gail's did not immediately respond to CNBC's request for comment.

- Karen Gilchrest

Ongoing tech disruption is set to be the 'largest IT outage in history,' cybersecurity researcher says

Troy Hunt, the respected cybersecurity researcher behind the popular password-breach monitoring service HaveIBeenPwned, labeled the ongoing global tech disruption as "the largest IT outage in history."

The CrowdStrike outage has caused cascading failures across multiple industries, with myriad airlines issuing ground stops, broadcast networks going off-air and critical services rushing to ameliorate the damage.

- Rohan Goswami

IT outage might not have an 'incredibly straightforward' fix, tech expert says

The ongoing global IT outage might not have an "incredibly straightforward" fix, according to Tom Lysemose Hansen, Chief Technology Officer at Norwegian cybersecurity company Promon.

"Crowdstrike's affected customers will have to effectively break into their own systems to get everything back online by logging into the admin console and booting their systems in safe mode," he said in emailed comments.

He added that CrowdStrike underpins the everyday operations of many organizations, "being present in anything from point of sale to ATMs as well as being used on Microsoft Windows systems."

CrowdStrike earlier on Friday said it was applying a fix to an identified and isolated defect in a single-content update for Windows hosts. The company did not immediately disclose what this measure would entail.

— Ruxandra Iordache

'We've never seen anything like this before,' Tenable's Satnam Narang says

The global IT outage is having a "profound impact," and nothing similar has ever been seen before, Satnam Narang, senior staff researcher at cybersecurity firm Tenable, told CNBC on Friday.

"It's very far reaching and we're still just in the beginnings of this right now," he said. Attempts to resolve the issue would take time, according to Narang.

"The challenge here is that security software — because it's doing its job to protect organizations — it has to have more privileged access to these machines. So ... while people may be seeing these as Windows failures, they're looking at it and seeing a little blue screen pop up, it's not actually a Windows issue, it's related to a faulty or bad update from those security software," he explained.

"We've never seen anything like this before, it's very unprecedented."

Speaking to CNBC from a hospital, Narang said health care was one of the key areas that has been impacted.

"Systems are offline which means, you know, patient records cant be accessed and medication can't be administered properly to patients," he said.

— Sophie Kiderlin

German institutions working with partners to resolve IT outage

German security institutions are working with international partners to resolve an IT outage that has affected air travel, banking and several companies, German Chancellor Olaf Scholz said Friday, according to Reuters.

Scholz, who is currently visiting Belgrade, went on to say that he had no further details to add on the situation at this time.

— Ruxandra Iordache

U.S. National Security Council is 'aware of the incident.'

A spokesperson for the U.S. National Security Council told CNBC that they were "aware of the incident and are looking into the issue and impacts."

CrowdStrike has a comprehensive government contracting practice.

— Rohan Goswami

'Blue screen of death' error message affects Microsoft users globally

Microsoft users around the world are being hit with the "blue screen of death" error message.

The U.S. tech giant was impacted by an update from cybersecurity firm CrowdStrike, which led to a major outage. Many other businesses have also been affected.

"We have been made aware of an issue impacting Virtual Machines running Windows Client and Windows Server, running the CrowdStrike Falcon agent, which may encounter a bug check (BSOD [blue screen of death) and get stuck in a restarting state. We approximate impact started around 19:00 UTC on the 18th of July," Microsoft said in an update at 5:40 a.m. ET.

"We can confirm the affected update has been pulled by CrowdStrike. Customers that are continuing to experience issues should reach out to CrowdStrike for additional assistance," the company added.

Read the full story here.

— Katrina Bishop

Swiss National Cyber Security Service says 'system failures' caused by CrowdStrike

Switzerland's National Cyber Security Service (NCSC) said it has received "corresponding reports from various companies and critical infrastructures in Switzerland" amid ongoing global system failures that the agency blamed on CrowdStrike.

"It is a faulty update or misconfiguration by the company CrowdStrike that is causing these system failures," the NCSC said in an emailed statement. "The NCSC is in contact with the affected companies."

CrowdStrike CEO George Kutz earlier in the day said that the company had deployed a fix to a defect found in an update for Windows hosts.

— Ruxandra Iordache

CrowdStrike CEO says company is resolving a defect

CrowdStrike is resolving a defect found in a single-content update for Windows hosts, the company's CEO George Kurtz said on social media on Friday.

He added that Mac and Linux hosts are not impacted by the disruption.

"This is not a security incident or cyberattack. The issue has been identified, isolated and a fix has been deployed," he said, without supplying a timeline for when the outage is likely to be fully resolved.

— Ruxandra Iordache

American Airlines says it has resumed operations

American Airlines said it has resumed operations after the Microsoft outage, though disruptions have continued for many airline passengers on Friday.

"Earlier this morning, a technical issue with a vendor impacted multiple carriers, including American. As of 5 a.m. ET, we have been able to safely re-establish our operation," American said in a statement. "We apologize to our customers for the inconvenience."

— Leslie Josephs

German hospitals cancel elective procedures

Two German hospitals on Friday canceled elective procedures and closed their outpatient units due to the global IT outage impacting businesses around the world.

In a statement that was translated by CNBC, the University Clinic Schleswig-Holstein said both of its hospital locations — Kiel and Lübeck — were impacted by the issues.

Care for the patients who were already in the hospitals, as well as emergency care, have been secured, the statement said.

— Sophie Kiderlin

FAA halts Delta, American and United departures because of outage

Departures of major U.S. airlines were halted on Friday as the carriers grappled with the Microsoft outage.

The Federal Aviation Administration had a ground stop in place for American, Delta and United as of Friday morning.

"The FAA is closely monitoring a technical issue impacting IT systems at U.S. airlines," the Federal Aviation Administration said in a statement. "Several airlines have requested FAA assistance with ground stops for their fleets until the issue is resolved." The agency said to monitor fly.faa.gov for updates.

Images posted on social media showed blue screens in airports as travelers complained that they were unable to retrieve bags or rebook flights, with some of them facing disruptions overnight, local time, when staffing was thin.

"We're aware of a technology issue with a vendor that is impacting multiple carriers. American is working with the vendor to resolve the issue as quickly as possible," American said on social media platform X.

--Leslie Josephs

India's IT minister 'in touch with Microsoft'

Indian IT Minister Ashwini Vaishnaw said his department was "in touch with Microsoft and its associates regarding the global outage."

"The reason for this outage has been identified and updates have been released to resolve the issue," Vaishnaw said on social media platform X.

The National Informatics Centre, a partner of the Indian government, is not affected, he added.

— Jenni Reid

Britain's public health service says most general practitioners' services suffering disruptions

Britain's National Health Service said it is experiencing disruptions in the majority of general practitioners offices as a result of the ongoing IT outage and an issue with an appointment and patient record system.

"The NHS has long standing measures in place to manage the disruption, including using paper patient records and handwritten prescriptions, and the usual phone systems to contact your GP."

It added that there is currently no known impact on emergency services, including the 999 life-threatening emergency phone service.

— Ruxandra Iordache

BBC children's channel unable to broadcast

CBBC, the children's television channel of U.K. public service broadcaster the BBC, was still offline at 10:11 a.m. in London (5:11 a.m. ET).

The screen displayed a message saying: "Sorry! Something's gone wrong." It was the only BBC channel impacted, according to updates from the organization.

Sky News was unable to broadcast earlier in the morning, but has since resumed service.

— Jenni Reid

Germany's Allianz says employees' ability to log into computers affected by outage

German insurer Allianz said its services have been impacted by the IT outage that has been enveloping businesses worldwide and is working to minimize the effect on customers and operations.

"We are currently experiencing a major outage that is impacting employees ability to log into their computers," it said by email. "It impacts multiple companies besides Allianz, specifically affecting the Windows login and is caused by an incident at our provider CrowdStrike."

The company did not immediately specify the number of employees affected.

— Ruxandra Iordache

Air travel passengers warned of delays

Airports and airlines have been issuing advice to passengers as the global IT issues hit their systems, with many warning of delays.

London's Gatwick Airport confirmed it began experiencing issues "early this morning" which were affecting "some airlines' check-in systems, baggage and security, including eGates."

"We are using our backup process, but some passengers may experience delays while checking in and passing through security. Passengers should still arrive for their normal check-in time, which is typically two hours ahead of the flight time for short-haul, and three hours for long-haul," the airport said in a statement.

Australia's Qantas said its flights were still operating with some delays.

Air New Zealand said it was dealing with a high number of customer calls and advised people to only contact customer service agents if they were due to fly within the next 48 hours. It said some customers would be experiencing payment issues, if they are customers of impacted banks.

Cathay Pacific said at 2:45 p.m. Hong Kong time (2:45 a.m. ET) that self-service check-in facilities at Hong Kong International Airport were not working.

"We ask all customers to check in online via our website or mobile app and obtain their mobile boarding pass before coming to the airport," the airline said. It also advised that its flight booking service is currently unavailable.

— Jenni Reid

Sky News temporarily unable to broadcast

Television channel Sky News was temporarily unable to broadcast live this morning, citing a "global technical issue."

David Rhodes, executive chairman of Sky News Group, said shortly after 9 a.m. London time that live broadcasting had been restored, but "without full capabilities."

Sky News and CNBC's parent organization, NBCUniversal, are both owned by Comcast.

— Jenni Reid

KLM suspends 'most' of its operation due to global computer outage

The Dutch arm of Air France-KLM said Friday it has been forced to suspend "most" of its operation due to a global computer outage.

The outage has made it "impossible to handle flights," KLM said in a statement. "We realize that, especially given the summer vacations, this is extremely inconvenient for our customers. We are working hard to resolve the problem."

Earlier Amsterdam's Schiphol Airport said a "global system failure at Microsoft" had disrupted flights to and from the airport. 

- April Roach

Microsoft says services 'continuing to see improvements'

In an update at 8:55 a.m. U.K. time (3:55 a.m. ET), Microsoft 365 said on social platform X that "multiple services are continuing to see improvements in availability as our mitigation actions progress."

According to a Microsoft web page tracking the status of its services, "users may be unable to access various Microsoft 365 apps and services." Issues are affecting apps including Microsoft Fabric, Teams, Purview, Defender, SharePoint and OneNote, according to the tracker.

— Jenni Reid

CrowdStrike, Microsoft shares lose ground

Shares of tech titans CrowdStrike and Microsoft were losing ground in premarket trading, after both reported significant outages that rippled across businesses worldwide.

CrowdStrike stock was down 14.08% at 09:27 a.m. London time, with Microsoft shares lower by 2.12%.

— Ruxandra Iordache

London Stock Exchange says investigating technical issues

London Stock Exchange Group on Friday said it is investigating technical issues after it was hit by a global IT outage affecting its pricing data and news communications.

In a notice on its website, LSEG said that it is "currently experiencing a 3rd party global technical issue, preventing news from being published on www.londonstockexchange.com."

"Technical teams are working to restore the service. Other services across the Group, including London Stock Exchange continue to operate as normal," the exchange group added.

LSEG's Eikon data platform was also affected by technical issues Friday morning.

When logging into the platform, a notice at the top of the site reads: "We're sorry for the inconvenience. You will need to restart workspace. If you need help, please contact us."

LSEG was not immediately available to provide a comment when contacted by CNBC Friday.

CrowdStrike rolls back update after major outage

Cybersecurity firm CrowdStrike suffered a major outage on Friday, the company told NBC, impacting businesses globally.

The outage resulted from an issue with the latest update, the company said. CrowdStrike is now in the process of rolling back that update globally.

— Katrina Bishop

Microsoft reports disruption

Microsoft's cloud services have been restored after suffering an outage, the company said on Friday.

The U.S. tech giant said late on Thursday that customers in the Central U.S. region may experience issues with multiple Azure services and its Microsoft 365 suite of apps. This could include "failures with service management operations and connectivity or availability of services."

On Friday, Microsoft said it determined the underlying cause and the majority of services were recovered. However, the company said that some customers may still experience issues in the region.

"A small subset of services is still experiencing residual impact," Microsoft said.

Read the full story here.

— Arjun Kharpal