Pirates without Borders: The Propagation of Cyberattacks through Firms’ Supply Chains

We document the supply chain effects of the most damaging cyberattack in history. The disruptions propagated from the directly hit firms to their customers, causing a four-fold amplification of the initial drop in profits. These losses were larger for affected customers with fewer alternative suppliers. Internal liquidity buffers and increased borrowing, mainly through bank credit lines, helped firms navigate the shock. The cyberattack also led to persisting adjustments to the supply chain network, with affected customers more likely to create new relationships with alternative suppliers and terminate those with the directly hit firms.