The biggest healthcare data breaches reported in 2021 each impacted more than 1 million patients, with more than 22.64 million patients affected overall. Considering the runner-up incident claimed 1.2 million breach victims, the year has seen some of the largest cybersecurity impacts in healthcare’s history. Not to mention, these totals don’t account for the more than 600 incidents reported to the Department of Health and Human Services in 2021, nor the unreported incidents and other healthcare breaches that may not fall under The Health Insurance Portability and Accountability Act.In total, four out of the top 10 biggest incidents were directly caused by vendors. The severity of the incidents reported this year highlight the sector’s ongoing challenges with vendors, the supply chain, and overall attack complexity. The largest breach reported this year best demonstrates these key weaknesses.Despite media outlets naming other incidents, the hack of the Accellion File Transfer Application reported in early 2021 was the biggest healthcare data breach this year. It’s an important distinction, as the hack highlights the sector’s biggest Achilles heel: third-party vendors.Threat actors cracked into longstanding, zero-day vulnerabilities in the FTA platform, which they used to pivot into connected provider systems and deploy a webshell named DEWMODE. The access was used to steal troves of sensitive information, used by the attackers to extort victims.That the attackers were so aptly — and stealthily — able to perform their nefarious acts should serve as a warning to all covered entities and business associates to prioritize identity and access management, as well as visibility and inventory challenges into the coming year. Security researchers have warned throughout the year, these attacks will continue to move the bar on their tactics, while leveraging evasive techniques.
1. Accellion: over 3.51 million individuals
As noted, the Accellion FTA hack had far-reaching implications for healthcare, including the risk posed by leveraging legacy technology and failing to promptly patch known security gaps. The attack was launched by the Clop ransomware group, notorious for actively targeting the healthcare sector.The hacking incident impacted at least 100 companies across all sectors, with the healthcare sector seeing the largest number of victims. Clop actors did end up leaking some of the exfiltrated data they stole from these victims, primarily from the U.S. and Canada.The largest healthcare victims were:- Centene subsidiaries: 1.3 million
- Health Net Community Solutions: 686,556
- Health Net of California patients: 523,709
- California Health & Wellness: 80,138
- University of Maryland, Baltimore: 30,468
- Health Net Life Insurance Company: 26,637
- Kroger: 1.5 million
- Trinity Health: 586,869
- Trillium Community Health Plan: 50,000
- The Southern Illinois University School of Medicine: 40,330
2. Florida Healthy Kids: 3.5 million patients
More than 3.5 million online applicants and enrollees of the Florida Healthy Kids Corporation (FHKC) were affected by a seven-year data breach caused by an FHKC vendor failing to patch multiple vulnerabilities in its website.The vendor informed FHKC that its security failure led to the access of thousands of applicant addresses. Some of the data was tampered with during the unauthorized access. A forensic review confirmed the website and its databases had several serious, unpatched flaws that allowed an attacker to access the site for many years before it was detected.The data exposure included names, Social Security numbers, financial information, dates of birth, family relationships, and secondary insurance data.3. 20/20 Eye Care Network: 3.3 million patients
In May, 20/20 Eye Care Network, also known as 20/20 Hearing Care Network, notified 3.3 million patients that their protected health information was accessed, downloaded, and possibly deleted, after an attacker gained access into its Amazon Web Services cloud storage bucket.The investigation couldn’t conclusively determine what data the hacker had actually accessed, just that they downloaded some patient information before completely destroying it. The affected data included SSNs, health insurance details, member ID numbers, and dates of birth.4. CaptureRx: 2.42M patients
HIPAA business associate CaptureRx faced a ransomware attack, which led to the access and exfiltration of a long list of its connected healthcare provider clients. The notice did not provide specifics on when the attack was launched, just that its investigation concluded in February.The investigation ended on March 19, which confirmed the stolen data included patients’ prescription details, names, and dates of birth. CaptureRx reported the breach to HHS as impacting 2.42 million individuals.Some of the affected covered entities included:- NYC Health + Hospitals: 43,000
- Faxton St. Luke’s Healthcare in New York: 17,655
- Jordan Valley Community Health Center: 12,000
- Trinity Twin City Hospital: 9,500
- Jones Memorial Hospital: 8,962
- Hudson Headwaters Health Network: 8,100
- UPMC Cole: 7,376
- Gifford Health Care in Vermont: 6,777
- Ascension St. Joseph Hospital: 5,807
- Brownsville Community Health Center: 4,258
- Thrifty Drug Stores: 3,958
- MetroHealth System
- Walmart




