Cellcom has confirmed that a cyberattack caused the week-long service disruption affecting customers across Wisconsin and Upper Michigan. Many users were unable to make calls or send texts during the outage.
In a message to customers, Cellcom CEO Brighid Riordan said the company had prepared for this type of incident. She explained that emergency protocols were activated immediately to limit the damage and restore service.
The telecom provider is now working with cybersecurity experts and has notified federal authorities. Service has started to return in some areas, but not all users are back online yet. The company hopes to restore full service by the end of the week, though it did not give a firm timeline.
Cellcom says the attack targeted part of its network that doesn’t store personal data. So far, investigators have found no signs that customer names, addresses, or payment details were exposed.
“We hit a major milestone last night,” Cellcom said. “We’re building on that success and working carefully to restore everything. We won’t rush anything that puts safety or trust at risk.”
The company hasn’t revealed the type of attack it faced. Still, the scale of the outage has led many to suspect ransomware. However, no known ransomware group has claimed credit.
Reporters trying to contact Cellcom for more details were unable to reach the company. Its public relations email appears to block messages from outside senders.
For now, Cellcom says it will continue to share updates as it brings services back online and investigates what happened.
