BlackCat’s McLaren Health Care Data Breach Exposes 2.2 Million Patients

McLaren Health Care is a network of 13 hospitals and three clinics serving the residents of north and central Michigan. They care for more than 732k lives by providing various services and network solutions, including a national cancer institute. Around August 2023, McLaren suffered a cyberattack—exposing the data of 2.2 million people. 

How Did the Attack Occur? 

An unauthorized actor purportedly gained access to McLaren’s network, but how the assailants achieved this is unclear. According to the Michigan Attorney General’s office, the ransomware criminals BlackCat allegedly premeditated the attack. Security may have intercepted the gang before their goals could be complete, based on no mention of encryption within the Michigan statement. Last month, BlackCat targeted Florida’s First Circuit Courts, resulting in the stalling of most activities. From that assault, we can speculate that the discovery of the unauthorized party may have come after service disruptions.

What Information Was Viewed or Stolen? 

The exposed information varies between individuals, with some having more credentials accessed than others. The consumer notice example provided to the Maine Attorney General’s Office suggests a list of potentially exposed data: full names, Social Security Numbers, date of birth, health insurance information, Medicare/Medicaid details, prescription and medication information, medical billing or claims credentials, medical record numbers, diagnostics, and treatment information. There is no evidence now that the stolen data is misused, but it is potentially within cybercriminals’ hands. 

How Did McLaren Health Care Admit to the Breach? 

The McLaren Health Care data breach purportedly occurred between July 28th and August 22nd, 2023; in August, McLaren professionals noticed suspicious activity within their systems, resulting in an investigation. The investigation concluded around October 10th, with the state attorney general’s offices and consumers notified. Notably, McLaren has sent notices only to those with valid mailing addresses; this means some individuals may miss or not receive their impact notice. 

What Will Become of the Stolen Information? 

According to the Maine filing, the McLaren Health Care data breach may impact 2,192,515 people. Presumably, the figure comprises patient data, but some employees could be in the mix. Those with data exposed in the attack can expect a mail notice in the coming weeks. If BlackCat is the source of this breach, they have likely sent a ransom demand to McLaren already. Regardless of McLaren’s response to the demands, patients should take action to protect themselves.  

What Should Affected Parties Do in the Aftermath of the Breach? 

BlackCat may further misuse the information leveraged in McLaren’s breach in future criminal plots; the only way to mitigate these potentials is by taking preventative steps to secure the data. Patients should monitor their accounts for suspicious activity, including Explanation of Benefits. Additionally, they should consider protecting their identity, as BlackCat has direct connections to the dark web. Patients should employ security measures on all their accounts, like strong passwords and multi-factor authentication. Precautions may not stop data misuse, but they can help mitigate its consequences, protecting you and your family.