Energy, water, financial, and communications systems essential to the nation.
The DarkSide ransomware group, operating from Russia, encrypted Colonial Pipeline's business systems, prompting the company to shut down the 5,500-mile pipeline that carries about 45 percent of East Coast fuel. CEO Joseph Blount authorized a $4.4 million ransom payment in bitcoin within hours. President Biden declared a regional emergency on May 9 and the pipeline resumed operations May 12. The attack accelerated federal pipeline cybersecurity rules and elevated CISA's critical-infrastructure mission.