Third-Party Data Breach Statistics

 

The Story Behind the Numbers

A third-party data breach happens when a company is compromised through a vendor, supplier, or partner with access to its data, rather than through its own systems. In 2024, just 92 vendors were responsible for breaches that hit 227 different companies. That ratio tells the real story: one compromised supplier can take down a long chain of businesses that never saw it coming.

The breached vendors came primarily from three industries: Software Services (26%), Technical Services (12%), and Healthcare Services (9%).

The attack methods varied by sector. In Software Services, ransomware led at 48%, followed by Unauthorized Network Access at 38% – collectively affecting 70 companies. In Technical Services, Unauthorized Network Access topped the list at 50%, with ransomware at 40%, hitting 25 companies. Healthcare vendors showed the starkest pattern: 75% of breaches came from Unauthorized Network Access, with ransomware accounting for the remaining 25%, across 18 affected companies.

When zooming out across all vendors, Unauthorized Network Access was the single most common attack method at 51.7%. Strip that out and focus only on known, named attack types – and ransomware dominated at 66.7%, with vulnerabilities at 15.4% and phishing at 7.7%.

Why This Data is Important

The companies on the receiving end of these third-party breaches were not random. Healthcare absorbed a disproportionate 41.2% of all impacts, followed by Finance & Insurance at 14.9% and Manufacturing at 14.0%. These are not low-stakes industries – they hold some of the most sensitive personal and financial data in existence.

What makes this pattern particularly troubling is how little progress vendors are making on defense. Of the 92 vendors involved in breaches, only 10 managed to improve their Cyber Rating by 3 or more points – an improvement rate of roughly 11%.

Understanding how VPN protocols work can help individuals add a layer of protection when connecting to third-party platforms, since encrypting your traffic limits what a compromised vendor can expose about you. For consumers, the key takeaway is this: your data does not have to be in a breach for it to be at risk. If a company you use shares data with a vendor – and that vendor is compromised – your information is in play. Taking steps to hide your IP address and limit your digital footprint reduces what’s exposed when a vendor is compromised.

Looking Ahead: Future Outlook

Third-party breaches are not slowing down. Ransomware now accounts for nearly two-thirds of all named attack methods targeting vendors, and the industries hit hardest – healthcare, finance, and manufacturing – are also among the least agile when it comes to vendor oversight. With only about 11% of breaching vendors showing measurable security improvement, the structural risk in supply chains is likely to grow before it shrinks.

Source & Methodology