The surge in cloud service adoption has led organizations to prioritize Multi-cloud strategies for optimized benefits and reduced costs. However, this shift introduces significant management and security challenges due to the complex, dynamic nature of multi-cloud environments. The increasing prevalence of cyber-attacks on Multi-cloud systems has raised concerns about their security and resilience, with attacks becoming more frequent and sophisticated, causing severe data breaches, downtime, and financial losses. The heterogeneous nature of multi-cloud environments introduces multiple attack surfaces and reduces data control, heightening vulnerabilities. Publicly exposed interfaces and cloud service brokers are particularly at risk due to misconfigurations and inadequate security. Criminals and hostile entities exploit these vulnerabilities to steal information and disrupt services. Consequently, the implications of these cyber threats extend beyond immediate financial impacts, leading to reputational damage, legal liabilities, and regulatory penalties that can have long-term effects on organizations. Given the complex and heterogeneous nature of multi-cloud networks, current security strategies may be insufficient to address the unique challenges posed by virtualized environments and diverse application workloads.

This qualitative study examines emerging cyber-attacks affecting the resilience of multi-cloud architectures and explores mechanisms to enhance Multi-cloud resilience against these attacks. The research employs surveys as its primary strategy, utilizing document studies and semi-structured interviews for data collection. Purposive sampling was used to select interview participants, with document analysis and thematic analysis applied to the document study and interview data, respectively.

The study categorizes cyber-attacks affecting multi-cloud resilience into two groups: those targeting service availability and those compromising multi-cloud resources. It details how these attacks undermine resilience and exploit specific vulnerabilities. The study recommends preventive and recovery mechanisms to defend against and recover from cyber threats, noting that the selection of these mechanisms is influenced by factors like cost, industry type, and data specifics.This study provide valuable insights for companies adopting Multi-cloud solutions, helping them to plan, design, and operate their Multi-cloud system with resilient against cyber attacks and guide Cloud Security architects to avoid possible vulnerabilities during multi-cloud design and deployments. This research contributes to the computer science community, establishing a foundation for future research in this domain.