According to individuals with knowledge of the situation, T-Mobile’s network was reportedly compromised as part of a detrimental Chinese cyber-espionage operation that effectively gained access to numerous U.S. and international telecommunications companies.
As part of a months-long campaign to monitor the cellphone communications of high-value intelligence targets, hackers affiliated with a Chinese intelligence agency were able to penetrate T-Mobile.
It is uncertain whether any information was obtained regarding the communications and conversations of T-Mobile customers.
The list of known victims of a cyber-espionage campaign by Chinese hackers, known as Salt Typhoon, has been expanded by the compromise of T-Mobile.
Some U.S. officials regard this campaign as historic and catastrophic in its scope and severity.
In October, the Journal previously reported that AT&T, Verizon, and Lumen Technologies were among the telecommunications companies that experienced an intrusion.
According to individuals with knowledge of the situation, the group employed sophisticated techniques to infiltrate the American telecom infrastructure by exploiting vulnerabilities in Cisco Systems routers.
Investigators suspect that the hackers employed artificial intelligence or machine learning to facilitate their espionage operations. Over the course of eight months or more, the assailants were able to infiltrate at least a portion of that infrastructure.
In the broader hacking campaign, assailants were able to access the cellphone lines of a variety of senior national security and policy officials within the U.S. government, as well as elected officials.
In what investigators believe may have significant national-security implications, the access enabled them to obtain call transcripts, unencrypted texts, and some audio from targets.
In addition, the hackers were able to access information from systems maintained by the carriers in order to comply with U.S. surveillance requests, which further exacerbated counterintelligence concerns.
Investigators are currently working to gain a comprehensive understanding of the incident, and they have stated that the Salt Typhoon group was responsible for the attack.
According to individuals with knowledge of the situation, the attackers did not access Lumen’s wiretap capabilities or obtain any customer data, despite the fact that the company does not offer wireless service.
The breaches also affected certain foreign telecommunications firms, including those in countries that maintain close intelligence-sharing partnerships with the United States, according to individuals familiar with the matter.
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