CBO Confirms Cybersecurity Breach, Suspected Foreign Hackers Behind Attack

The U.S. Congressional Budget Office (CBO) has confirmed it was hit by a cybersecurity breach believed to be the work of a suspected foreign hacker. The incident has raised concerns that sensitive government data and private communications between lawmakers and CBO analysts may have been compromised.

CBO spokeswoman Caitlin Emma said in a statement that the agency “identified the security incident, took immediate action to contain it, and has implemented additional monitoring and new security controls to further protect the agency’s systems.” She added that the agency continues its work for Congress as investigators look into the breach.

The Washington Post first reported the incident, citing unnamed officials who said the intrusion was discovered only a few days ago. Lawmakers were warned that hackers may have accessed emails, internal chats, and exchanges between CBO staff and congressional offices. Some offices have temporarily paused email communication with the CBO as a precaution.

According to internal alerts, the hackers might have viewed confidential discussions on pending legislation, economic forecasts, and draft reports. The CBO, a nonpartisan agency with around 275 employees, provides independent analysis on economic and budgetary issues for nearly every bill considered by Congress. Its reports—known as “CBO scores”—help determine how proposed laws could affect the national debt and government spending.

While the CBO has not publicly identified the attackers, U.S. officials told CNN that the breach is suspected to be the work of Chinese state-backed hackers. The Chinese Embassy in Washington denied the allegation, stating that Beijing “consistently opposes and combats all forms of cyberattacks.”

The attack comes amid a series of recent cyber intrusions targeting U.S. government agencies. In late 2024, hackers linked to the Chinese group Silk Typhoon reportedly infiltrated systems at the U.S. Treasury Department and the Committee on Foreign Investment in the United States (CFIUS).

Cybersecurity experts say the CBO breach highlights the ongoing risks faced by federal institutions that handle sensitive data and policy information. The full scope and impact of the intrusion are still under investigation, but the incident underscores the growing digital threats facing even smaller government agencies in the global cyber conflict.