Bluesky says another DDoS attack caused its recent outage

Bluesky says its recent day-long disruption was caused by a distributed denial-of-service (DDoS) attack that flooded the site with junk traffic. The social network confirmed the incident in a post on Monday, saying the attack had taken place over the previous 24 hours.

“We have upgraded our defenses in response, and we continue to monitor the situation,” Bluesky said in the post, without disclosing further details. A spokesperson for Bluesky did not immediately respond to TechCrunch’s questions about the attack.

DDoS attacks involve pummeling a website or server with large amounts of junk traffic to overload its resources and knock it offline. These attacks often rely on large numbers of hijacked internet-connected devices — enlisted into a residential proxy network or a botnet — to harness their unused bandwidth and flood web servers.

Security researchers discussing the attack in the IFIN public forum report that Iran-backed attackers have claimed responsibility. Iran has increased its attacks on U.S. businesses and critical infrastructure since the start of the U.S. and Israel-led war earlier this year.

This is the latest large-scale DDoS attack to affect the social network in recent months. In April, Bluesky was hit by a prolonged series of outages caused by a similar flood of web traffic. It’s unclear if the attacks are linked.

Why it matters

This is Bluesky’s latest large-scale DDoS attack in recent months, coming amid reports of a broader rise in Iran-linked attacks on U.S. businesses and infrastructure since the war with Israel began — though it’s not yet clear whether this attack and April’s are connected.