Here's the official statement...
We have been working around the clock to investigate claims being made that T-Mobile data may have been illegally accessed. We take the protection of our customers very seriously and we are conducting an extensive analysis alongside digital forensic experts to understand the validity of these claims, and we are coordinating with law enforcement.
We have determined that unauthorized access to some T-Mobile data occurred, however we have not yet determined that there is any personal customer data involved. We are confident that the entry point used to gain access has been closed, and we are continuing our deep technical review of the situation across our systems to identify the nature of any data that was illegally accessed. This investigation will take some time but we are working with the highest degree of urgency. Until we have completed this assessment we cannot confirm the reported number of records affected or the validity of statements made by others.
We understand that customers will have questions and concerns, and resolving those is critically important to us. Once we have a more complete and verified understanding of what occurred, we will proactively communicate with our customers and other stakeholders.
Although T-Mobile has yet to confirm access to customer data, Motherboard says the sample data it was shown proved valid.
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