Citrix vulnerability behind Change Healthcare cyber attack, CEO claims

Laptop showing logo of UnitedHealth Group, parent company of Change Healthcare
(Image credit: Getty Images)

UnitedHealth Group CEO Andrew Witty is expected to tell a US House subcommittee that hackers exploited Citrix remote access software during a devastating cyber attack against Change Healthcare in February. 

Witty is due to appear before the House Energy and Commerce committee tomorrow, and a copy of his written testimony describes UnitedHealth’s response to the ALPHV/BlackCat threat collective’s attack.

According to the chief exec, after the ransomware attack occurred  on 21 February, UnitedHealth immediately severed connectivity with Change Healthcare’s data centers as to limit the potential for further infection, claiming no external environments were accessed.

In his summary of the timeline of the attack, Witty claimed a Citrix portal used for remote access was the initial entry point used by the attackers.

“On February 12, criminals used compromised credentials to remotely access a Change Healthcare Citrix portal, an application used to enable remote access to desktops. The portal did not have multi-factor 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.”

The testimony does not elaborate further on the specific nature in which the credentials were compromised or which security flaw they exploited, and it is still unclear whether or not the attackers leveraged a security flaw in the Citrix portal to gain access.

2023 was a challenging year for Citrix, with the firm having revealed a string of high-profile security incidents.

Notably, the cloud computing company was forced to issue a security advisory in late 2023 after a critical vulnerability affecting its NetScaler products, known as Citrix Bleed, was being leveraged to target a number of healthcare institutions across the US.

Citrix Bleed continued to be a pervasive security threat for organizations around the world through November 2023, with major firms including Boeing, Allen & Overy, and the Industrial and Commercial Bank of China (ICBC), all said to have been hit with successful ransomware attacks as a result of the flaw.]

ITPro approached Citrix for comment regarding Witty’s statement but did not receive a response.  

“One of the hardest decisions I’ve ever had to make” – could banning ransom payments work?

Underpinning the payment systems used in healthcare organizations across the US, Change Healthcare processes 50% of all medical claims in the region, highlighting the material impact.

The UnitedHealth Group confirmed it had paid a ransom to the culprits, one of the largest in US history, on 22 April after researchers monitoring crypto wallets linked to the ALPHV group reported a sizable transaction in early April.

Witty said he took the decision to pay the ransom in order to get disrupted healthcare services back up and running as soon as possible, noting the difficult position executives are faced with when subjected to ransomware attacks.

“As chief executive officer, the decision to pay a ransom was mine. This was one of the hardest decisions I’ve ever had to make. And I wouldn’t wish it on anyone.”


Witty said due to the ongoing nature and complexity of the data review being undertaken, it could be another several months before enough information is available to identify and notify individuals whose data was impacted by the attack.

Discouraging and even prohibiting companies from paying ransoms has been one approach to crack down on the ransomware industry. Proponents of this tactic argue that the move will limit revenue streams for cyber criminals. 

Others, however, have argued that criminalizing business leaders to try and discourage ransom payments could end up doing more harm than good.

Discussing the prospect of a potential ban on payments,Ian Thornton-Trump, CISO at threat intelligence company Cyjax, told ITPro he thinks attempts to proscribe ransoms could end up backfiring and further hinder executives ability to respond to cyber attacks.

“I think what you need to understand is that [executives] also have a fiduciary responsibility to act on behalf and in the best interests of [their] company, and if that’s now going to be criminalized because you pay a ransom to keep people employed, I think that’s an absurd policy.”

Thornton-Trump suggested governments could look into mechanisms that could be used to support businesses targeted with ransomware attacks, and this relief could help them avoid the last resort of paying the ransom.

“What we need to do is create a structure similar to the idea where there is some relief for the business that suffered the cyber attack and to give it an alternative to paying the ransom”, he explained.

“An arbitrary ban serves no purpose, when it’s the last resort for a business that is either going to close its doors, unemploy people, create a tax loss, and blow the economy”.

Solomon Klappholz
Staff Writer

Solomon Klappholz is a Staff Writer at ITPro. He has experience writing about the technologies that facilitate industrial manufacturing which led to him developing a particular interest in IT regulation, industrial infrastructure applications, and machine learning.