A new cryptocurrency miner has been detected infecting servers worldwide. The miner, dubbed MassMiner, is exploiting several known vulnerabilities in its malicious campaigns:
- An Oracle WebLogic flaw known as CVE-2017-10271
- A Windows SMB flaw known as CVE-2017-0143
- An Apache Struts flaw known as CVE-2017-5638
How Is the MassMiner Campaign Infecting Users
According to researchers from AlienVault, this malicious campaign is using these exploits to infect unpatched and outdated systems to install the MassMiner Monero miner. The flaws are rated as highly efficient and their deployment shows that cybercriminals know very well what they are doing.
CVE-2017-10271 has already been exploited in other attacks. In February this year researchers detected a Monero miner targeting database servers using this vulnerability. Security reports show that the flaw is one of the most actively exploited against servers.
CVE-2017-0143 is another very popular exploit also known as EternalBlue which was leveraged by the NSA and was leaked online last year. The bug has been used in a number of famous ransomware campaigns such as WannaCry and NotPetya. In the context of the current MassMiner operation, cybercriminals are using the EternalBlue exploit to install the DoublePulsaw backdoor on unpatched systems.
As for the Apache Struts bug, CVE-2017-5638, it’s also a known and already leveraged bug. Previously, attackers were using CVE-2017-5638 to obtain nearly absolute control over web servers used by banks, government agencies, and big Internet companies. The attacks were disclosed in March 2017 by Vicente Motos from Hack Players, who wrote that “If you run it against a vulnerable application, the result will be the remote execution of commands with the user running the server”.
In addition, this is the same vulnerability that was used against Equifax last summer.
More about the MassMiner Monero MinerA Attack
Shortly put, the MassMiner Monero miner runs the exploits against vulnerable systems, and is also brute forcing access to Microsoft SQL Servers using SQLck.
Once MassMiner has been installed, it sets up the system to avoid detection making itself persistent. According to AlienVault’s detailed analysis:
- The malware copies itself to ‘C:\Windows\ime\taskhost.exe’ and the Startup folder to obtain persistence;
- Schedules tasks to execute its components;
- Modifies ACL to grant full access to certain files in the system through running cacls.exe, with: cmd /c schtasks /create /sc minute /mo 1 /tn ‘Flashfxl’ /ru system /tr ‘cmd /c echo Y|cacls C:\Windows\TEMP\Networks\taskmgr.exe /p everyone:F
- Kills the Windows Firewall with: cmd /c net stop MpsSvc
In addition, the sample analyzed by the researchers also installed the well-known Gh0st backdoor, which communicates with the domain rat.kingminer[.]club.
Two Monero wallets belonging to the attackers and used for cashing out have been identified:
How to Detect and Remove Coin Miner Viruses such as MassMiner
Cryptocurrency miners use various methods to infiltrate a system. In the case of MassMiner, three major vulnerability exploits were used, meaning that patching your system is the first and most important tip for keeping your system safe.
Some miners are fileless and remain on your PC, while others run suspicious executable processes as a system task in the background. One thing is clear though – if you have a high usage of your PC’s GPU or CPU components, recommendations are to immediately follow the removal instructions below to detect and remove the particular miner.
Be advised that although you can follow many guidelines and protection tips, like the ones beloww, the best method to remove miners and to detect them before they have even been activated is to use and advanced anti-malware protection. Such software will help you automatically remove any miner virus by scanning your PC for its definitions thanks to which your system immediately becomes protected against this form of malware.