Ukraine knocked out key Yandex data centers. The fallout is being felt across Russia.

Ukraine targeted three of Yandex's six data centers in Russia, located in Sasovo, Kaluga, and Vladimir, in response to Russian attacks on Ukrainian data centers. These facilities, dubbed Yandex's "iron heart," sustained damage. Operations at two centers—Sasovo and Vladimir—ceased entirely, while Kaluga suffered significant disruption.

Other websites and media outlets also experienced restrictions. Users abroad reported issues with Yandex's apps. As of October 12, restoration was still pending. The strikes led to outages in various services, including Yandex Mail, Pay, Disk, Go, and more. Yandex Cloud clients also suffered disruptions, with some reports of problems accessing external platforms like a cafe chain's app, media websites, and a continuous glucose monitoring service.

Yandex attempted to allay concerns by stating user funds remained secure, though an estimated restoration timeline remained uncertain. The outage impacted users outside Russia as well, with disruptions in Kyrgyzstan, Kazakhstan, Uzbekistan, Armenia, Belarus, and Serbia. Yandex's supercomputers, crucial for AI model training, were among the affected data centers.

Cybersecurity analysts noted a 49% decrease in Russian bot traffic following the strikes, possibly contributing to reduced online hostility. Yandex reacted by warning users of potential outages and later restoring access to core services. The company allocated backup cloud services and added a force majeure clause to its user agreement.

Yandex shares plummeted after the initial strikes, and experts warned of rising costs due to equipment replacement and infrastructure adjustments. Other data center owners also fortified their facilities against drone attacks, leading to additional expenses. The Kremlin has not commented on the strikes, but Russia's digital development minister described it as unprecedented.