AT&T Inc. has revealed another breach of customer data, separate from a previous incident earlier this year. According to CBS News, it included records of calls and texts for nearly all its mobile-phone users over a six-month period in 2022 and is considered one of the largest breaches of private communications data.

The company stated that the hack, previously undisclosed, affected customers of wireless service providers using AT&T's network between May 1, 2022, and October 31, 2022. Additionally, records from January 2, 2023, were compromised for a small number of customers.

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AT&T's Recent Data Breach

CNN clarified that the stolen data does not include the contents of the calls and messages, personal information such as birth dates and Social Security numbers, or the times of the calls. However, the breach did involve telephone numbers that an AT&T or MVNO (Mobile Virtual Network Operator) cellular number interacted with during the affected periods. 

Although the data doesn't include customer names, AT&T noted that publicly available online tools could potentially connect these numbers with people's identities. 

Despite the extensive nature of the breach, AT&T stated that it does not believe the compromised information has been released publicly. The company has initiated an investigation involving cybersecurity experts and has taken steps to close off the illegal access point. 

As recently shared by VCPost, AT&T is working with law enforcement to implement identity theft protection and believes at least one individual involved in the hack has been apprehended. 

Following the announcement, AT&T shares dropped 2% in premarket trading, while Snowflake Inc., the third-party cloud platform identified as the source of the breach, saw a 4.1% decline in its shares.

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