Microsoft has warned that China-based cyber criminals are currently targeting companies and individuals to install a “double extortion” new ransomware strain that emerged last month.
As early as January 4, attackers started exploiting the Log4j ‘Log4Shell’ flaw in VMware’s Horizon product in internet-facing systems.
“Our investigation shows that successful intrusions in these campaigns led to the deployment of the NightSky ransomware. These attacks are performed by a China-based ransomware operator that we’re tracking as DEV-0401,” Microsoft said in a statement on Monday.
In addition, HAFNIUM, a threat actor group operating out of China, has been observed utilising the vulnerability to attack virtualisation infrastructure to extend their typical targeting.
In these attacks, HAFNIUM-associated systems were observed using a DNS service typically associated with testing activity to fingerprint systems.
The ‘Log4j’ vulnerabilities represent a complex and high-risk situation for companies across the globe.
This open-source component is widely used across many suppliers’ software and services.
“Sophisticated adversaries (like nation-state actors) and commodity attackers alike have been observed taking advantage of these vulnerabilities. There is high potential for the expanded use of the vulnerabilities,” said Microsoft.
In January, the company started seeing attackers taking advantage of the vulnerabilities in internet-facing systems, eventually deploying ransomware.
At this juncture, said the tech giant, customers should assume broad availability of exploit code and scanning capabilities to be a real and present danger to their environments.
“Due to the many software and services that are impacted and given the pace of updates, this is expected to have a long tail for remediation, requiring ongoing, sustainable vigilance,” the company added.
A report last week from the digital arm of the UK’s National Health Service (NHS) said that attackers are targeting VMware’s Horizon server software.
VMware has detailed which versions of Horizon components are vulnerable or not, and the different remediation steps for each if they are vulnerable.