Many of us have come to expect data breaches as an everyday part of life. After all, your account information is only as safe as the companies you're doing business with, and every passing year makes it increasingly evident how little attention is paid to such matters. T-Mobile already suffered one of the year's most notable data breaches over the summer, and just days before the end of 2021, it's reportedly been hit with another.

According to The T-Mo Report, leaked internal documents show that a small number of accounts were victims of unauthorized access this month. Affected users either had their data viewed by an unknown individual — including names, addresses, phone numbers, plan rates, and number of lines — or fell victim to an unauthorized SIM swap, with a third subset of users facing both. T-Mobile confirmed in these documents that customers who contacted their support team were able to regain access to their SIM.

For its part, the company has contacted individuals who were targeted in this breach, alerting them to specify what was or wasn't viewed and highlighting that this hacker stole no payment or password data to its knowledge. However, T-Mobile has yet to report any specifics about how many customers were directly affected.

Thankfully, this breach sounds much smaller than the one the company was hit with over the summer, in which millions of accounts were accessed after the hacker called its security protection "awful." It seems possible that this is another example of poor security practices, though we'll have to wait until T-Mobile delivers more information.