Jones Day Law Firm Says Hackers Accessed Some Clients’ Data (1)

Hackers have breached Jones Day and accessed the files of 10 clients, the law firm said on Monday.

A prolific cybercriminal group known as Silent took credit for the attack, listing Jones Day among its victims on an extortion website.

“Jones Day recently experienced a cyber ‘phishing’ incident in which an unauthorized third party accessed a limited number of dated files for 10 clients,” spokesperson Dave Petrou said in a statement. “All impacted clients have been notified.”

The identities of the affected clients weren’t immediately clear. Hackers also stole data belonging to Jones Day in 2021.

The law firm has represented a huge number of large American companies, including Goldman Sachs Group Inc., McDonald’s Corp. and General Motors Co. The firm was hired in February to defend JPMorgan Chase in a case in which President Donald Trump sued the bank for its closure of his accounts in 2021.

The hacking group Silent specifically targets American law firms, stealing data and extorting them, according to a 2025 FBI alert. The hackers take advantage of the “the highly sensitive nature of legal industry data,” according to the FBI.

The gang is known to target law firms with phishing attacks and masquerade as other businesses in order to trick victims into downloading malicious software, according to the FBI.

(Updated with additional context starting in fifth paragraph.)

To contact the reporter on this story:
Patrick Howell O’Neill in Washington at patoneill1@bloomberg.net

To contact the editors responsible for this story:
Jeff Stone at jstone183@bloomberg.net

Andrew Martin

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