In this paper, we study the experiences of practitioners in sectoral Computer Security Incident Response Teams (CSIRTs)—specialized teams that mediate between national cybersecurity authorities and the sector constituency. Through interviews with 18 professionals connected to the Informatiebeveiligingsdienst (IBD-CSIRT) for Dutch local governments, we uncover tensions in how key services are valued. For vulnerability notifications, while the CSIRT staff consider them a core service, many constituents hardly mention them, and systemic gaps in information forwarding mean that crucial alerts often never arrive. We extend these insights with 5 interviews across other sector CSIRTs and a validation workshop with 7 participants, all security officers from sector CSIRTs, revealing shared challenges in balancing technical expertise with sector knowledge, building trust-based relationships, and navigating institutional bottlenecks. Our findings contribute the first systematic account of how sector CSIRT professionals understand and perform their role, highlighting the tensions in providing sector-wide support to professionals with differing security needs.

In this study, we present a 532-day longitudinal analysis of LockBit 3.0’s leak site. We track 1,856 victims across multiple states-countdown, data publication, deletion, and relisting-and reconstruct a structured, three-stage extortion lifecycle: (1) pre-listing negotiation, (2) countdown negotiation, and (3) post-leak monetization. We find that $8.5 \%$ of countdownstate victims are deleted before their data is published, suggesting private settlements. In the post-leak phase, victims with price tags exhibit significantly more variable deletion timing compared to those without, despite sharing the same median exposure. This indicates that LockBit actively manages some listings after data publication, potentially extending monetization or negotiation efforts.We also measure the operational impact of law enforcement actions-including Operation Cronos and affiliate arrests-on LockBit’s infrastructure and victim activity. While the group rapidly restored services after takedowns, we observe a sustained decline in new victim onboarding, reduced infrastructure redundancy, and delayed payment behavior, suggesting long-term weakening.To our knowledge, this is the first empirical study to model a ransomware extortion lifecycle based on continuous monitoring of leak site behavior. Our findings provide actionable insights into ransomware monetization tactics, negotiation patterns, and post-takedown adaptation.

Many cybercriminal entrepreneurs lack the skills and techniques to provision certain parts of their business model, leading them to outsource these parts to specialized criminal vendors. Online anonymous markets, from Silk Road to AlphaBay, have been used to search for these products and contract with their criminal vendors. While one listing of a product generates high sales numbers, another identical listing fails to sell. In this paper, we investigate which factors determine the performance of cybercrime products.