Key Takeaways from the 2025 Third-Party Breach Report

Written by: ​​Ferhat Dikbiyik, Chief Research & Intelligence Officer

Every breach tells a story. In 2024, that story was about third-party vulnerabilities becoming the preferred entry point for attackers. From ransomware attacks that threatened supply chains to credential misuse that compromised entire industries, third-party breaches surged in both scale and sophistication.

Black Kite’s 2025 Third-Party Breach Report takes a deep dive into these incidents, analyzing the most significant third-party breaches of 2024 to identify the key trends shaping the future of cybersecurity. This year’s findings highlight critical shifts in the third-party risk landscape: ransomware affiliates are becoming more aggressive, unauthorized network access remains the most exploited attack vector, and regulatory frameworks are driving improvements — but not evenly across industries.

5 Takeaways from the 2025 Third-Party Breach Report

For cybersecurity leaders looking to adapt their strategies for the year ahead, here are a few notable findings from this year’s report — and what they mean for your approach to third-party risk management.

1. A shift to continuous risk monitoring

In 2024, the Cleo File Transfer ransomware attack was a wake-up call that exposed the shortcomings of traditional third-party risk management. Attackers exploited unpatched vulnerabilities in widely used file transfer software, impacting dozens of organizations across industries. Traditional security assessments failed to catch these risks, but proactive monitoring tools could have flagged these vulnerabilities before attackers did.

For example, for too long, third-party risk management (TPRM) has relied on security questionnaires. Organizations track response rates, completion metrics, and compliance checklists — but breaches keep happening. The problem? These assessments measure vendor effort, not actual security posture, and for one point in time at that..

Meanwhile, ransomware groups aren’t wasting time with paperwork. They’re studying supply chains, buying marketing intelligence, and doing everything they can to learn more about their victims and their supply chains. Questionnaires are no defense against this kind of sophisticated, intentional approach. 

Organizations need to move beyond static assessments and embrace real-time risk intelligence to detect vulnerabilities before they’re exploited. Instead of relying solely on vendors’ self-reported security measures, organizations should implement continuous monitoring tools that provide real-time visibility into third-party risks. During the Cleo File Transfer ransomware campaign, for example, Black Kite’s FocusTags™ helped organizations identify at-risk vendors and implement rapid mitigation strategies to prevent further breaches.

2. Affiliates are changing the rules of ransomware

Ransomware operations underwent a major shift in 2024, driven by changes in the underground cybercrime economy. The February attack on Change Healthcare didn’t just impact pharmacies, doctors, and hospitals — it reshaped the entire ransomware market. A payment dispute between an affiliate and a major ransomware group led to a structural change, where affiliates gained greater control and financial incentives. 

This affiliate-led model has fueled a spike in ransomware activity. Now, instead of centralized ransomware groups leading the charge, affiliates are operating with more autonomy, deploying multiple types of ransomware and significantly increasing the frequency of attacks. 

Healthcare bore the brunt of these attacks in 2024, accounting for over 40% of all third-party breaches. And unlike ransomware groups that historically followed an informal “twisted code of conduct” — where healthcare organizations were considered off-limits — modern affiliates have no such boundaries. They prioritize financial gain over all else, choosing targets based on likelihood to pay. The Cencora ransomware attack, for instance, allegedly resulted in a $75 million ransom payment, exposing sensitive patient data and revealing the cascading impact of third-party breaches.

This shift in ransomware tactics means organizations can no longer rely on past attack patterns to predict future threats. With financially motivated affiliates now driving attacks, businesses must invest in tools designed to proactively monitor and manage third-party risks to ensure a rapid response to disruptive events.

3. Regulations are driving cybersecurity improvements

Regulatory frameworks like DORA, HIPAA, and GDPR have been catalysts for critical risk management improvements, particularly in industries with strict compliance mandates. According to our findings, among vendors that experienced a breach and subsequently improved their cyber rating by at least 3 points, 72% serve the healthcare industry — an indication that regulatory enforcement is driving significant improvements in incident response and vendor risk management practices.

However, not all industries are keeping pace. Only 14% of vendors with improved scores following a breach support the financial services sector. Similarly, only 14% of vendors in the manufacturing sector showed progress in enhancing their cyber ratings.

The progress observed in sectors like healthcare, where regulations drove notable improvements, serves as a model for other industries to follow. But regulations aren’t enough on their own either. While regulatory frameworks establish baseline security standards, they must be backed by proactive risk management strategies. Organizations that implement continuous third-party risk monitoring, leverage real-time threat intelligence tools, and enforce vendor accountability through contractual security requirements are significantly better positioned to identify and mitigate emerging threats.

4. Defining unauthorized network access

Unauthorized network access accounted for over 50% of publicly disclosed third-party breaches in 2024. But what does that really mean? Too often, “unauthorized access” is used as a vague, catch-all explanation when organizations lack clarity on the root cause of an attack or choose not to disclose specific details. This makes it difficult to determine whether breaches were caused by stolen credentials, misconfigurations, or unpatched vulnerabilities.

The lack of transparency in incident reporting presents a serious challenge for CISOs. Without a clear picture of how attackers infiltrated a system, security teams struggle to remediate vulnerabilities and prevent future breaches. Instead of driving meaningful improvements, these incidents often fuel blame games and reactive security postures.

Given the sheer volume of breaches attributed to unauthorized access, security leaders must push for deeper analysis and clearer reporting. Creating a culture of transparency in incident reporting can help security teams better understand the root causes of unauthorized network access breaches, enabling more effective prevention strategies.

5. Building a resilient third-party risk management strategy

While we can’t predict exactly what’s next, there’s a lot we can learn from last year’s third-party breaches. By analyzing the trends, cybersecurity leaders can fine-tune their strategies to stay ahead of emerging threats. What’s clear from this year’s 2025 Third-Party Breach Report is that a proactive, collaborative approach to third-party risk management is now essential.

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As we move into 2025, relying on reactive measures is no longer enough. Organizations must embrace real-time risk assessments, improve vendor communication using tools like Black Kite Bridge™, and invest in actionable remediation intelligence. Cyber threats are evolving fast, and so must the tools and strategies used to combat them. By adapting to these changes in the third-party risk landscape, companies can build a stronger, more resilient security posture and better protect themselves against the next wave of cyber threats.

Dive deeper into the insights — read the full 2025 Third-Party Breach Report now.