- The Salt Typhoon hack is one of the largest attacks on US telecommunications ever, officials say.
- The yearslong attack originated in China and targeted major telecom companies like AT&T and Verizon.
- The NSA says it believes Chinese hackers were targeting senior US political figures.
US security officials have warned that millions of people's personal information could be at risk after a yearslong hacking campaign originating in China.
The US government started investigating the hack in the summer after Microsoft — which named the hack the Salt Typhoon — sounded alarms about anomalies.
Speaking to reporters on Saturday, White House Deputy national security advisor Anne Neuberger said that while data belonging to millions of Americans was likely compromised, the hack targeted senior US officials.
"We believe the calls they recorded and took was really more focused on very senior political individuals," she said.
A report from the Congressional Research Office said Chinese hackers may have sought access to presidential candidates' communications. "With that access, they could potentially retrieve unencrypted communication (e.g., voice calls and text messages)," the report says.
A senior NSA official said in October that hackers from China accessed information from AT&T, Verizon, and Lumen Technologies, according to NBC.
Senate Intelligence Committee Chairman Mark Warner told The Washington Post that the hack is the "worst telecom hack in our nation's history by far."
"This is an ongoing effort by China to infiltrate telecom systems around the world, to exfiltrate huge amounts of data," Warner told the outlet.
The New York Times reported that hackers from China went undetected inside American telecommunications companies for over a year and obtained a nearly complete list of phone numbers that the Justice Department monitors in its "lawful intercept" system. The lawful intercept system is what allows law enforcement, through a court order, to wiretap or "bug" phone calls.
The FBI warned that all US citizens should use a cellphone that automatically updates its operating system and use encryption and multifactor authentication for email and social media accounts.
Neuberger said in an earlier press call on Wednesday that the government does not believe any of the targeted telecom companies have "fully removed" the Chinese hackers from their networks, and communications are still at risk. Senior White House officials on the call said the hack has been ongoing for "likely one to two years."
"President Biden has been briefed multiple times on this compromise," Neuberger told reporters. She added that the White House "has made it a priority for the federal government to do everything it can to get to the bottom of this."
Neuberger said that White House leaders are meeting three times a week to discuss the hack.
The Senate Commerce Subcommittee will hold a hearing on December 11 to discuss security threats to communications networks and review best practices for providers to mitigate consumer risks. The committee will focus on the Salt Typhoon attacks in the hearing.