UnitedHealth’s Change Healthcare subsidiary paid $22 million in ransom to the attackers who broke into its systems in February, according to Congressional testimony today. And it revealed that the scope of the breach could be much larger than anyone imagined — even as it remains unclear whether the ransom payment secured the data from being used in follow-on attacks.

UnitedHealth’s CEO Andrew Witty testified before the US House Energy and Commerce Committee today after weeks of disruption at the nation’s largest health insurer, during which a series of concerning revelations about the breach came to light.

Poor Security: Stolen Credentials, No MFA

For instance, the BlackCat/ALPHV ransomware affiliate hackers who broke into Change in February didn’t have to work very hard to achieve success. According to the testimony, they were able to use previously compromised credentials to log into Change’s Citrix platform, possibly obtained via an initial access broker — and that account wasn’t protected with multifactor authentication (MFA).

Also, the attack was discovered when BlackCat deployed ransomware on Feb. 23, but the attackers actually had unfettered access to the environment for more than a week before that, indicating a woefully lacking intrusion detection apparatus.

“On February 12, criminals used compromised credentials to remotely access a Change Healthcare Citrix portal, an application used to enable remote access to desktops,” according to Witty’s prepared testimony, released ahead of the hearing. “The portal did not have multifactor authentication. Once the threat actor gained access, they moved laterally within the systems in more sophisticated ways and exfiltrated data. Ransomware was deployed nine days later.”

In his oral testimony, Witty also spilled additional details that, when added to the unchanged Citrix credentials (it’s evident that the company doesn’t have processes in place to track compromised credentials that may be part of prior breaches) and lack of MFA, point to an overall lack of security maturity. For instance, the company has had to perform a complete rebuild on its systems, even after decrypting files; and its backups weren’t sequestered with network segmentation or infrastructure gapping, so the attackers were able to lock those up too, blocking any recovery path from the initial attack.

“This attack exemplifies … why it is important to have controls in place to regularly review access entitlements. Compromised credentials or not, the attackers were able to leverage an account that gave them access to carry out their attack,” said Piyush Pandey, CEO at Pathlock, in an emailed statement. “In this case, MFA could have been an effective gate to the proliferation of this attack. The additional layers of security would make the breach more challenging … in a broader view, this is a great example of the importance of layering technologies and processes, such as MFA, combined with strong application access controls and data security technologies, such as data masking, which can help mitigate widespread data breaches.”

Impact on Data Security for PII, PHI Unclear

Also in the oral testimony today, Witty confirmed that the adversaries made off with a large amount of personally identifiable information (PII) and personal health information (PHI). While Witty didn’t talk hard numbers, the data in question “could cover a substantial proportion of people in America,” he said. He did not address whether the data is still at risk.

To put that comment into perspective, “Change Healthcare processes roughly 15 billion healthcare transactions annually, and a third of Americans’ patient records pass through its digital doors,” Sen. Ron Wyden (D-Ore.) noted in a statement ahead of the hearing.

The senator added, “Change specializes in moving patient data from doctor’s office to doctor’s office, or to and from your insurance company. That means medical bills that are chock full of sensitive diagnoses, treatments, and medical histories that reveal everything from abortions to mental health disorders to diagnosis of cancer to sexually transmitted infections. Military personnel are included in this data.”

Wyden also warned that the breach could end up being a clear national security threat.

“I don’t think it’s a stretch [that] the impact here rivals the 2015 hack of government personnel data from the Office of Personnel Management, which the FBI called a ‘treasure trove’ of counterintelligence information for foreign intelligence services,” he said.

UnitedHealth’s Next Steps Unknown

UnitedHealth is the nation’s largest insurer and the fifth largest company in the US, with $324 billion in revenue and housing data on 152 million individuals. The breach is easily the largest cyber incident to ever affect the healthcare landscape. But it’s unclear what’s next for Change and UnitedHealth; Wyden pointed out that existing regulations, such as they are, carry only “slap on the wrist” enforcement actions. The companies also haven’t detailed how or when they plan to improve their cyber defense postures (UnitedHealth has no cybersecurity executive on its board).

Meanwhile, in the weeks since the breach was made public, the company has seen copycat activity from the RansomHub cybercrime outfit, and because the incident wreaked havoc across the healthcare supply chain, the Department of Health & Human Services responded with a policy game plan to address cyber-risk at insurers (though it still does not require healthcare orgs to meet minimum cybersecurity standards). It is almost certain that there will be additional developments in the saga going forward.

Source: www.darkreading.com