Malware that ends up downloading two cryptocurrency miners — 32-bit and a 64-bit — to Windows computers that it infects, has been spotted by researchers at security firm Trend Micro.
Researchers Johnlery Triunfante and Mark Vicente wrote that the malware in question was taking advantage of a vulnerability in Oracle's WebLogic server which the company had patched back in October.
Last month, as iTWire reported, unpatched Internet-facing Oracle WebLogic servers running on both Windows and Linux were being infected with cryptocurrency-mining malware.
While the practice of malware authors using cryptocurrency mining instead of ransomware is now a widely used tactic, Triunfante and Vicente said the two-miner variation made this malware — which they dubbed Coinminer_MALXMR.JL-PS — stand out from the crowd.
{loadposition sam08}The method of infection was not specified but once the flaw was exploited and the payload delivered, it left the infected host with dual miners which worked to mine the monero cryptocurrency.
Once the payload was run, it would download three files to the machine. These would then go through their own programmed processes ending with the presence of the two miners.
"Our analysis of the latest payload shows that the architecture of Windows OS plays a part in deciding which coin miner will run," Triunfante and Vicente wrote.
"The first monero miner is a 64-bit variant which will execute on a corresponding 64-bit Windows device. But, if the device is running a 32-bit Windows version then the second coin miner will run instead."
As usual, when the scripts run, they tended to slow down the infected systems and affect performance, the researchers added.
"A coin-mining malware tries to infect as many devices as possible since it takes an extraordinary amount of computing power to substantially mine any cryptocurrency," they wrote.
"With two payload systems, both of which are capable of starting automatically and daily, the malware developers of this particular exploit have more chances to infect machines and use them for cryptomining."