NEW YORK — Major Wall Street firms faced attempted cyberattacks this week, according to three sources familiar with the matter, driving a cautious tone across U.S. equity markets. The Nasdaq fell 0.8 percent to 26,363, the S&P 500 dropped 0.2 percent to 7,724 and the Dow Jones Industrial Average gained 0.5 percent to 54,349.
The attempts did not compromise core systems or customer data, sources said, but they expose growing cybersecurity risk across the financial sector. Operational risk events of this kind tend to widen credit default swap spreads on bank debt — bond investors demand a concession when systemic vulnerabilities surface, and duration risk on long-dated bank paper rises alongside perceived credit risk.
Federal regulators are monitoring the situation, a Treasury Department official said, stressing the need for stronger defenses. The Federal Reserve is also focused on financial stability, particularly the resilience of critical market infrastructure and interbank liquidity.
Higher cybersecurity spending could pressure bank earnings, compressing net interest margins and complicating balance sheet duration management. Increased funding costs for short-term debt would, in turn, influence the shape of the yield curve.
Industry leaders are expected to address cybersecurity resilience and threat intelligence sharing at the Financial Services Information Sharing and Analysis Center summit next month. The Treasury Department will release its annual financial stability report in late September, which typically includes a section on cyber threats and their potential impact on market infrastructure.
