Security researchers from F5 Networks spotted a sophisticated malware campaign, tracked as Zealot campaign (after the name zealot.zip, one of the files dropped on targeted servers), targeting Linux and Windows servers to install Monero cryptocurrency miners.
The campaign was detected by security researchers from F5 Networks, who named it Zealot, after zealot.zip, one of the files dropped on targeted servers.
Hackers are using a wide arsenal of exploits to compromise the servers and install the malware, including the same code used in the Equifax hack
F5 Networks experts observed threat actors scanning the Internet for particular unpatched servers and hack them with two exploits, one for Apache Struts (CVE-2017-5638) and one for the DotNetNuke ASP.NET CMS (CVE-2017-9822).
“F5 threat researchers have discovered a new Apache Struts campaign. This new campaign is a sophisticated multi-staged attack targeting internal networks with the NSA-attributed EternalBlue and EternalSynergy exploits.” states the analysis from F5 Networks.
“We have dubbed the campaign “Zealot” based on the name of the zip file containing the python scripts with the NSA-attributed exploits. As we continue to research this campaign, we will update this publication.”
The exploit for the Struts vulnerability includes malicious code for targeting both Linux and Windows machines at the same time.
Once the hackers infected a Windows machine, they used the EternalBlue and EternalSynergy exploits (both exploits belong to the huge trove of data belonging to the NSA that was leaked by the Shadow Brokers earlier this year) for lateral movements in the target network.
In the last stage of the attack, threat actors would use PowerShell to download and install the Monero miner.
The attack against Linux servers sees attackers using Python scripts that appear to be taken from the EmpireProject post-exploitation framework, to install the same Monero miner.
“Zealot seems to be the first Struts campaign using the NSA exploits to propagate inside internal networks. There were other malware campaigns like NotPetya and WannaCry ransomware, and also Adylkuzz cryptominer launching attacks by directly scanning the Internet for SMBs to exploit with the NSA tools the ShadowBrokers released.” continues the analysis.
“The Zealot campaign, however, seems to be opening new attack vector doors, automatically delivering malware on internal networks via web application vulnerabilities.”
The researchers reported that the amount that was paid for the miner address associated with the Zealot campaign was approximately $8,500 USD, we cannot exclude that crooks also used other Monero wallets.
The researchers warned of the possible change for the final-stage payload, they could use the same campaign to deliver ransomware.
Another curiosity emerged from the analysis it that the attackers appear to be big fans of the legendary StarCraft game, in fact, many of the terms and file names used for this campaign are characters of the game (i.e. Zealot, Observer, Overlord, Raven).
“The level of sophistication we are currently observing in the Zealot campaign is leading us to believe that the campaign was developed and is being run by threat actors several levels above common bot herders,” concluded the analysis.
(Security Affairs – Zealot Campaign, Monero miners)