Artificial intelligence (AI) has triggered a spiral upgrade of cross-domain collaboration between digital commerce, finance, and cybersecurity, following a three-stage iterative logic: resource aggregation (integrating cross-domain data, technology, and capital through AI), risk governance (jointly mitigating cross-domain risks via AI-powered tools), and ecosystem value addition (expanding the scale and value of the cross-domain ecosystem through iterative optimization). This review synthesizes 7 key studies (2022-2026) to unpack the operational mechanism of each stage and the spiral upgrade logic: resource aggregation lays the foundation by breaking resource silos (e.g., multi-tenant infrastructure integrating SME resources, LSTM models integrating financial data); risk governance ensures sustainability by addressing cross-domain risks (e.g., privacy-enhancing technologies [PETs] mitigating privacy risks, multi-agent reinforcement learning [MARL] balancing security and financial risks); ecosystem value addition realizes iteration by amplifying cross-domain value (e.g., inclusive growth from SME participation, sustainable value from ESG integration). Findings reveal that the spiral upgrade is driven by mutual feedback—resource aggregation generates new risks that require risk governance, and risk governance optimizes resource allocation to promote ecosystem value addition; AI modularity and privacy technologies are the core drivers of spiral iteration; SMEs are the key beneficiaries and amplifiers of the spiral upgrade. This model provides a dynamic perspective on cross-domain AI collaboration, guiding researchers, practitioners, and policymakers to foster continuous value creation across sectors.