Last week, the US Department of Treasury confirmed it had suffered a cyberattack, attributed to Chinese hackers, that had successfully gained access to several workstations.
A new report from Bloomberg has revealed devices belonging to Secretary Janet Yellen and other top officials were also impacted by the attack, which reportedly compromised over 400 computers and more than 3,000 unclassified files.
The Treasury reports the hackers were able to access "law enforcement sensitive" information related to investigations carried out by the Committee on Foreign Investment in the United States (CFIUS) but the attack did not breach classified systems.
Alarm bells ringing
While the hack appears to have mostly accessed non-classified data, the devices of Secretary Janet Yellen, Deputy Secretary Wally Adeyemo and Acting Under Secretary Brad Smith were affected.
Bloomberg reports that those close to the matter believe fewer than 50 files on Yellen’s device were compromised.
According to the Treasury’s report, the attackers appeared to focus on the Treasury’s role in sanctions, intelligence and international affairs but were unable to access email or classified systems.
The threat actor behind the attack has been identified as a Chinese state-sponsored actor known among cybersecurity professionals as Silk Typhoon and UNC5221, according to the report.
The Chinese Government denies any involvement in the attack, with spokeswoman Mao Ning telling reporters that “China opposes all forms of hacking, and in particular, we oppose spreading China-related disinformation motivated by political agenda” during a news conference in Beijing last month.