Bluesky suffered a 24-hour DDoS attack that caused outages. A pro-Iran hacker group claimed responsibility for the disruption.Bluesky experienced a sophisticated DDoS attack that disrupted its services for about 24 hours, starting on April 15.Bluesky is a decentralized, open-source microblogging social media platform similar to X (formerly Twitter). It allows users to post short messages, images, and videos (up to 300 characters) while providing more control over algorithms, data, and moderation.The attack disrupted feeds, notifications, threads, and search, causing intermittent outages. A pro-Iran hacker group, called 313 Team (aka “Islamic Cyber Resistance in Iraq”), claimed responsibility, highlighting growing threats against social media platforms and the impact of coordinated disruption campaigns.“Our team received a report of intermittent app outages at about 11:40pm PDT on April 15, 2026. They worked through the night to mitigate a sophisticated Distributed Denial-of-Service (DDoS) attack, which intensified throughout the day.” Bluesky announced. “We have not seen any evidence of unauthorized access to private user data.”The company found no signs of data breaches and confirmed it limited the impact of the attack and avoided prolonged outages.313 Team is a pro-Iran hacktivist group tied to politically driven cyber activity like DDoS attacks, defacements, phishing, and data-leak claims. It targets public services, government and symbolic platforms to create disruption and amplify geopolitical tensions. Analysts link it to the broader Iran-aligned ecosystem, sometimes close to state interests. However, the group often exaggerates its impact, so claims should be treated with caution.Follow me on Twitter: @securityaffairs and Facebook and MastodonPierluigi Paganini(SecurityAffairs – hacking, Islamic Cyber Resistance in Iraq)