T-Mobile has been subjected to yet another cyberattack following a big data breach in August. According to documents revealed by The T-Mo Report, attackers gained access to "a small number of" users' accounts this time. The damage appears to be far less serious this time. It appears that just a small percentage of consumers are affected. There is no further information regarding what transpired, with the records just stating that some information was leaked.
Customers who have been affected fall into one of three categories. First, a client may have only been impacted by a CPNI leak. This information could include the billing account name, phone numbers, the number of lines on the account, account numbers, and rate plan information. That's not ideal, but it's far less damaging than the August incident, which exposed client social security numbers.
The second category into which an impacted consumer may fall is having their SIM swapped. In order to get control of a phone number, a malicious actor will alter the physical SIM card linked with it. This can and frequently does result in the victim's other online accounts being accessed through two-factor authentication codes supplied to their phone number. According to the document, consumers who were affected by a SIM swap have now had that action reversed. The final category consists of both of the previous two. Customers who were affected may have had their private CPNI accessed as well as their SIM card swapped.
When it comes to account security, T-Mobile does not have the finest track record. As previously stated, a huge data breach occurred earlier this year in August, exposing information on roughly 50 million users across both post-paid and prepaid accounts. The stolen files contained crucial personal information such as first and last names, dates of birth, Social Security numbers, and driver's licence / ID numbers - the kind of information you could use to open a new account or hijack an existing one. It did not appear to include "phone numbers, account numbers, PINs, or passwords."
Affected customers, who appear to be few in number, have received letters warning them of the unlawful activity on their accounts. Memos have also been placed on those impacted accounts so that reps may see them when they log in.
"We informed a very small number of customers that the SIM card assigned to a mobile number on their account may have been illegally reassigned or limited account information was viewed. Unauthorized SIM swaps are unfortunately a common industry-wide occurrence, however, this issue was quickly corrected by our team, using our in-place safeguards, and we proactively took additional protective measures on their behalf," a T-Mobile spokesperson said.
