Cyberattack Takes Down Wisconsin-Based Mobile Carrier

A cyberattack has caused a week-long outage at a mobile carrier in Wisconsin, preventing users from texting and receiving or making phone calls. 

Cellcom today officially attributed the outage to a “cyber incident” after originally blaming the problem on a technical issue. “The cyber incident that we’re experiencing is segmented to the voice and texting part of your service,” CEO Brighid Riordan said in a video to customers.

The hackers are apparently still trying to attack the company’s systems. They “are working to do damage just as hard as we are working to prevent it,” Riordan said. But in some good news, no customer information appears to have been stolen. 

Cellcom didn’t immediately respond to a request for comment, making it unclear if the attack involves ransomware, which can encrypt entire fleets of computers. But in a letter to customers, Riordan said the company is working with “outside cybersecurity experts, notifying the FBI and Wisconsin officials, and working around the clock to bring systems safely back online.”

The outage began late on May 14, sparking numerous complaints from Wisconsin-based customers of Cellcom, which provides affordable cell phone plans for consumers and businesses. “I have 42 lines with them for my company and family. This outage has cost us thousands,” wrote one user on Reddit. 

On Monday, Cellcom said it had restored texting for customers. Plus, Cellcom customers should be able to make and receive voice calls to each other. “As a gesture of accountability and thanks, we are covering outage service fees for the customers that continue with us,” it says.

The company’s service page is also publishing updates about Cellcom’s effort to restore its system. The page notes that affected users should try turning on the phone’s airplane mode for 10 seconds or restarting their device if they’re still unable to connect.

About Michael Kan

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I’ve been working as a journalist for over 15 years—I got my start as a schools and cities reporter in Kansas City and joined PCMag in 2017.

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