Ransomware — a type of malware that encrypts an organization’s data or locks them out of their systems — continues to be a significant threat to financial institutions (FIs), wreaking havoc on their business continuity, operations, vendor management program, and finances. Ransomware hit record numbers in Q1 2025, with more than 2,000 victims. The average ransomware payment reached over $500,000 in Q4, a 16% increase from the previous quarter.
In this post, we’ll discuss how to protect your FI against ransomware and what to do if you or one of your vendors experiences an attack.
Related: A Cybersecurity Assessment Tool Designed for Financial Institutions
In December 2023, ransomware attackers infiltrated a third-party business continuity planning and disaster recovery provider. The incident quickly snowballed, impacting another unit of the vendor’s parent company, a data processor for credit unions. This led to widespread outages, non-operational data centers, interrupted online and mobile banking services, and many unhappy members.
How can you protect your FI against ransomware attacks like the one described? While not entirely unavoidable, there are some key steps you can take to mitigate ransomware-related risks.
Related: Will Your Vendors Fall Victim to Ransomware and Other Cybersecurity Threats?
It happened: You or one of your financial institution’s critical third-party vendors has fallen victim to ransomware.
Below is a framework that applies to both internal incidents and third-party ransomware events.
Ransomware attacks — internal and external — can spread quickly. Isolate the infected system to prevent the malware from spreading laterally across your network. Disconnect compromised endpoints and begin the incident response process.
If a vendor falls victim to a ransomware attack, evaluate your connection. If you use software as a service (SaaS), you probably don’t have to sever it. However, if a vendor system integrates with your systems, you’ll likely want to disconnect and even shut down your machines.
Regardless of the incident’s source, determining what was affected is critical:
If a third party experiences an attack, request a detailed formal incident report from the vendor to understand their mitigation and recovery process.
Related: Incident Tracking: 4 Benefits & 5 Best Practices
Legal guidance is essential for both internal and external ransomware incidents. Before informing the authorities, contact legal counsel.
Financial institutions and their employees are increasingly edgy when it comes to cybersecurity, and it’s possible a staff member could overreact to a false positive. Your FI doesn’t want to draw attention to a vendor breach if the vendor’s ransomware issue doesn’t directly impact your FI.
Ransomware can simultaneously impact multiple critical systems. A strong business continuity plan (BCP) should account for this by ensuring a coordinated response across IT, cybersecurity, compliance, legal, and business units.
While the BCP doesn’t need to be event-specific, it must integrate with your incident response plan, disaster recovery, and communications strategy to address data loss, service delays, and other potential impacts. Recovery priorities may shift during an attack, making scenario testing essential to ensure your BCP holds up under pressure.
Related: Does Your BCP Have a BCP?
Breaches make headlines, so your FI needs to be prepared to answer consumer questions about what happened. In the immediate phase, ensure your customer service representatives can accurately respond to customer or member calls.
Don’t assume general liability or business interruption insurance covers cyber events. If you have cyber coverage, review its scope carefully, as it may exclude vendor breaches or cyber terrorism. Know whether you have first-party coverage (direct costs like notifications, business interruption, and extortion) or third-party coverage (claims from customers, partners, or vendors).
Too often, FIs don’t implement what they have learned from incidents. After a ransomware incident:
Do you know how to manage incidents to minimize downtime, mitigate risk, and ensure regulatory compliance and operational resilience?
Ensure you’re following best practices with our incident response plan checklist.