Computer networks of smartwatch and electronics firm Garmin were offline Friday in an incident which raised concerns of a ransomware attack affecting both its aviation and fitness app services.

The company said on Twitter its website and Garmin Connect fitness app had been offline since Thursday. It said the "flyGarmin" site used for aviation databases was also down.

Garmin offered no explanation for the outage but security analysts said a likely reason could be ransomware, a technique used by hackers to encrypt data and extort funds.

"We are currently experiencing an outage that affects Garmin Connect," the company tweeted.

Garmin Aviation, which provides cockpit navigation and communication services, said on its Facebook page its "flyGarmin" website and mobile app were down.

A suspected ransomware attack has shut down networks of Garmin, which makes smartwatches as well as navigation services for aviation
A suspected ransomware attack has shut down networks of Garmin, which makes smartwatches as well as navigation services for aviation ANP / Rob Engelaar

"We are working to resolve this issue as quickly as possible and apologize for this inconvenience," the company said.

Brent Callow, a threat analyst at the security firm Emsisoft, said he had no firsthand knowledge but that it "certainly has all the hallmarks of a ransomware incident."

"There is really no other event that would be likely to cause such widespread disruption and cause a company to immediately shut down everything from its online services to its production line," Callow said.

The security news website Bleeping Computer reported that a source familiar with the incident said Garmin was attacked by the WastedLocker ransomware.

Some reports have linked the malware to a Russian cybercriminal group known as Evil Corp.

Ransomware