Threat of Cryptojacking Still an Issue

In November of 2018 Forbes ran an article about the increase of cryptojacking. At the time the Cyber Threat Alliance (CTA) was indicating a 629% increase of infections in just the short time between Q1 to Q2 of 2018. Threats had grown from an estimated 400,000 (Q4 2017) infections to 2.5 million infected machines in Q2 of 2018. 2019 is still showing growth in cryptojacking threats.

The number of tools available to bad actors has grown. For example the Russian threat, WebCobra, that McAfee Labs researchers found, was able to drop one of two different payloads based on architecture it detected on the infected machine.

The threats are continuing to become more sophisticated as well.  360 Total Security researchers have released the details of the newer PsMiner malware. Designed to exploit known vulnerabilities in servers running ElasticSearch, Hadoop, Redis, Spring, Weblogic, ThinkPHP, and SqlServer to spread from server to server to mine for Monero.

The worm uses a file called Systemctl.exe written in the Go language to bundle then download the exploit modules and to attack Windows servers. In addition to the exploits, PsMiner has the ability to brute force its way in to a system. When it detects weak or default credentials, it can utilize a brute force password cracking component.

Once it PsMiner has access to a system, it then uses a PowerShell command to download a WindowsUpdate.ps1 with a malicious payload and master module that will drop the Monero miner on the system. The malware then copies itself into the temp directory and create a scheduled task called “Update service for Windows Service” that will run once every 10 minutes to prolong and refresh the infection. Using the XMRig CPU miner and a custom mining profile while using Living-off-the-Land (LotL) techniques, the worm can persist for some time.

This also shows a level of sophistication to which the bad actors have access.  Another example of this type of attack sticking around is the eight Microsoft Store apps found dropping cryptojacking malware on systems: Fast-search Lite, Battery Optimizer (Tutorials), VPN Browsers+, Downloader for YouTube Videos, Clean Master+ (Tutorials), FastTube, Findoo Browser 2019, and Findoo Mobile & Desktop Search.

These Apps have been since removed from the Microsoft store, but show a troubling pattern of predatory behavior.  Estimates are indicating that there have been ten times more organizations affected by cryptojacking than ransomware just last year. It is clear that cryptojacking is still a threat to consider in 2019.

Sources
https://www.bleepingcomputer.com/news/security/malware-spreads-as-a -worm-uses-cryptojacking-module-to-mine-for-monero/

https://www.forbes.com/sites/rachelwolfson/2018/11/13/cryptojackingon-the-rise-webcobra-malware-uses-victims-computers-to-minecryptocurrency/#20183346c336

https://blog.malwarebytes.com/cybercrime/2018/02/state-maliciouscryptomining/