A cryptocurrency-mining botnet has recently added a scanner for the BlueKeep RDP protocol vulnerability, Intezer’s security researchers have discovered.
Dubbed WatchBog, the botnet has been active since late 2018 and previously only targeted Linux systems. Largely undetected at the moment, the malware has infected over 4,500 Linux machines in new attacks observed since early June, and it appears that its operators are looking to expand their reach.
The group has been targeting known vulnerabilities in Linux systems, and has recently expanded its implants list to target more servers. It now includes recently published exploits, such as Jira’s CVE-2019-11581, Exim’s CVE-2019-10149, and Solr’s CVE-2019-0192, Intezer says.
Additionally, the crypto-mining botnet now includes a scanner for BlueKeep, a Windows-based kernel vulnerability tracked as CVE–2019-0708 and which allows an attacker to remotely execute code on a vulnerable system.
Function name similarities suggest that the tool is a Python port from a scanner available on GitHub. At the moment, the botnet only appears to be creating lists of vulnerable systems, the security researchers say.
The BlueKeep security flaw impacts Windows versions ranging from Windows 2000 to Windows Server 2008 and Windows 7, but a patch has been available for several months.
While there have been no attacks observed in the wild targeting the vulnerability to cause a crash and achieve code execution, information on how to turn the crash into the RCE has emerged online earlier this week, security researcher MalwareTech warns.
BlueKeep Warning: someone published a slide deck explaining how to turn the crash PoC into RCE. I expect we'll likely see widespread exploitation soon.https://t.co/MG2IZfy5B5
— MalwareTech (@MalwareTechBlog) July 22, 2019
The researcher also reveals that the slides include information on how to do a pool spray, which was apparently the most difficult part of the exploit. While information on other aspects of the vulnerability’s exploitation were already publicly available, this was the only missing element, it seems.
With WatchBog now able to scan for the BlueKeep vulnerability, it becomes clear that it will be only a matter of time before the botnet adds an exploit as well.
“The Jira, Solr and BlueKeep scanner modules were all added in the time frame of 13 days. WatchBog seems to be accelerating the incorporation of new functionalities as of late,” Intezer notes.