Jillian Deutsch, Todd Shields, Jake Bleiberg, and Jennifer Jacobs of The Wall Street Journal report that the outage was triggered by work on a network expansion, not by a cyber attack. They write:
AT&T Inc. said a widespread outage that took hours to resolve Thursday was caused by “an incorrect process” while expanding the wireless network.
The software issue interrupted wireless service for hundreds of thousands of subscribers and prompted the FBI and US Department of Homeland Security to investigate the outage.
“Based on our initial review, we believe that today’s outage was caused by the application and execution of an incorrect process used as we were expanding our network, not a cyber attack,” an AT&T spokesman said in a statement. “We are continuing our assessment of today’s outage to ensure we keep delivering the service that our customers deserve.”[…]
“In my experience, this type of outage can negatively impact financial results in the quarter in which it occurs and cause short-term lost goodwill with customers,” David Heger, an analyst at Edward D. Jones & Co., said in an email. “However, it does not have a longer term impact on the business.”
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