Qilin, also known as Agenda, is a Russian-speaking ransomware-as-a-service operation active since 2022 and highly prolific by 2025 with over 1,000 victims. It uses a flexible platform enabling affiliates to customize attacks targeting local files, network shares, and virtual machine infrastructure, including ESXi hosts. Initial access is commonly gained via phishing, stolen credentials, vulnerable internet-facing systems, and remote management tools. The group employs a double-extortion model, encrypting data and threatening to publish stolen information on their blog and WikiLeaksV2 platform. Notable incidents include the 2024 Synnovis attack impacting UK healthcare services. Qilin is linked to other threat groups and has spawned derivative operations, some maintaining affiliate status while operating independent leak sites.
