WASHINGTON (Reuters) – A Chinese hacker has compromised even more U.S. telecommunications companies than previously known, including Charter communications (NASDAQ:), Consolidated Communications and Windstream, the Wall Street Journal reported late Saturday, citing people familiar with the situation.
The hackers also used unpatched network devices from the security vendor. Fortinet (NASDAQ:) and hacked major Cisco Systems (NASDAQ:) network routers, the newspaper reports.
In addition to deep intrusions into AT&T (NYSE:) and Verizon (NYSE:), hackers also penetrated other networks owned by Lumen Technologies and T-Mobile, according to the report.
China has denied involvement in such activities and accused the United States of spreading disinformation.
There are growing concerns about the size and scope of reports of Chinese hacking of U.S. telecommunications networks, and questions about when companies and the government will be able to provide reassurance to Americans on the matter.
The report added that US national security adviser Jake Sullivan told telecommunications and technology executives at a secret White House meeting in the fall of 2023 that Chinese hackers had gained the ability to shut down dozens of US ports, power grids and other infrastructure at will.
China-linked cyberespionage operation Salt Typhoon targeted AT&T and Verizon systems, but U.S. wireless carrier networks are now safe as they work with law enforcement and government officials, the companies said last week in their first admission of the attacks.
Lumen said it no longer saw evidence of malicious actors on its network and that customer data had not been accessed. T-Mobile said it stopped recent attempts to break into its systems and protected sensitive customer information from being accessed, according to the Journal.
Verizon told the newspaper that a small number of high-profile customers in government and politics were targeted by the attacker and that those people had been notified.
Vandana Venkatesh, Verizon’s chief legal officer, told the newspaper that “Verizon has restrained its actions related to this particular incident.”
Cisco and Fortinet declined to comment to the newspaper.
It was previously reported that the targets of the Salt Typhoon were officials associated with the presidential campaigns of Democrat Kamala Harris and Republican Donald Trump.