AWS us-east-1 outage (October 2025)
A fifteen-hour outage on October 19 and 20, 2025, caused by a DNS resolution fault in the DynamoDB service, which interrupted thousands of applications worldwide.
Large cloud providers split their regions into independent availability zones, and customers that spread their workloads across zones believe they are protected. But a region also shares common control services, and some global services depend on a single legacy region. When one of these core services fails, all zones fail together and the customer's redundancy is of no use. For a cyber insurer, this is the accumulation scenario through a single point of failure: a non-malicious event that hits thousands of unrelated insureds at once. The outage was also a reminder that dependent business interruption cover for an IT provider must be read word by word, since many policies distinguish an attack from a mere technical failure.
From 11:49 p.m. on October 19, 2025 to 3:01 p.m. on October 20, Pacific time, about fifteen hours, AWS services in the us-east-1 region were disrupted after DNS resolution of the DynamoDB endpoint failed. More than one hundred forty AWS services were affected, and with them games, messaging apps, payment platforms and banking services around the world.
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