Microsoft's security team revealed a new ransomware that is deployed in human-operated attacks. It uses "brute force" against a target company's systems management server, and mainly has targeted the healthcare sector amid the COVID-19 crisis.

According to a series of tweets published by the tech giant on May 27, the human-operated ransomware attack, named "PonyFinal", requires hackers to break the security scheme of corporate networks in order to deploy the ransomware manually.

That means PonyFinal doesn't rely on tricking the users into launching the payload through phishing links or emails.

A Java-based ransomware attack

The Java-based Pony Final deploys a Java Runtime Environment, or JRE. Evidence found by Microsoft shows that attackers use information stolen from the systems management server to target endpoints where JRE is already installed.

The report further states that the ransomware is delivered via an MSI file that contains two batch files, including the payload that will be activated by the attacker.

Phillip Misner, research director of Microsoft Threat Protection, clarifies that there are other human-operated ransomware campaigns such as Bitpaymer, Ryuk, Revil, and Samas. PonyFinal was first detected at the beginning of April.

More than one group of attackers are using PonyFinal

The report highlights that authorship cannot be attributed to a single group of attackers, as several hacker groups are using this same form of ransomware.

Speaking with Cointelegraph, Brett Callow, threat analyst at malware lab Emsisoft, provided the following feedback on PonyFinal:

"Human-operated ransomware such as PonyFinal is not unusual and nor is its delivery method which, according to Microsoft, is 'thru brute force attacks against a target company's systems management server.' Attacks on internet-facing servers are not at all unusual and account for a significant percentage of ransomware incidents. But they're also mostly preventable as such attacks typically only succeed because of a security weakness or vulnerability."

Callow adds that companies can significantly reduce the likelihood of being successfully attacked by adhering to best practices: using multi-factor authentication, patching promptly, and disabling PowerShell when possible.

Latest ransomware attacks in the midst of the coronavirus pandemic

Ransomware attacks continue to be carried out in different parts of the world in the midst of the COVID-19 crisis, with many targeting healthcare companies.

Cointelegraph reported on March 30 that operators of Ryuk ransomware continue to target hospitals.

On May 7, hackers reportedly infected the IT infrastructure of the largest private hospital in Europe, Germany-based Fresenius, with a ransomware known as Snake.