(Reuters) – FBI leaders warned that hackers who breached AT&T (NYSE: ) last year likely stole months of agents' call and text logs, prompting an urgent effort to protect the identities of confidential informants, Bloomberg News reported on Thursday.
The breach, which is believed to have compromised all FBI devices using AT&T's public safety service, included the agents' cell phone numbers and the numbers they used to call and text, according to a document reviewed by Bloomberg and its interviews with current and former officials criminal proceedings.
Last July, AT&T said the company suffered a massive hacking incident when data from about 109 million customer accounts containing call and text records dating back to 2022 was illegally downloaded in April.
FBI officials told agents across the country that details of their use of the telecom operator's network were likely among the billions of records stolen, the report said, adding that while the hacked records did not reveal the content of the communications, they could link investigators to their secret sources. message added.
An FBI spokesman told Reuters the agency “has a serious responsibility to protect the identity and safety of confidential human resources who provide information every day that keeps the American people safe, often at risk to themselves.”
In a follow-up message, a spokesman said the FBI has a responsibility to protect the identity of “any individual who contacts the FBI and provides information.”
AT&T spokesman Alex Byers told Reuters that after “criminals stole customer data last year, we worked closely with law enforcement to mitigate the impact on government operations.”
The breach follows broader concerns about cyber espionage targeting US telecommunications networks. On January 10, US national security adviser Jake Sullivan said the US had taken action in response to cyber espionage operations against US telecommunications firms linked to China.
U.S. telecommunications firms Verizon (NYSE: ) and AT&T said late last year that their networks had been targeted by cyber hackers but were now secure because they were cooperating with the U.S. government and law enforcement.
