Malware

MrbMiner cryptojacking campaign linked to Iranian software firm

Sophos experts believe that an Iranian company is behind a recently uncovered MrbMiner crypto-jacking campaign targeting SQL servers.

Sophos researchers that investigated the recently uncovered crypto-mining campaign targeting SQL servers with MrbMiner malware believe that it was conducted by an Iran-based company.

In September, a group of hackers launched brute-force attacks on MSSQL servers with the intent to compromise them and install crypto-mining malware dubbed MrbMiner.

According to security firm Tencent, the team of hackers has been active over the past few months by hacking into Microsoft SQL Servers (MSSQL) to install a crypto-miner. The threat actors used a botnet to target thousands of MSSQL installations with the MrbMiner. The name of the miner comes after one of the domains used by the group to host their malicious code.

Once the hackers gained access to a system, they downloaded an initial assm.exe file to achieve persistence and to add a backdoor account for future access. Upon creating the account, the malicious code connects to the C2 to download a Monero (XMR) cryptocurrency miner that runs on the local server.

The Sophos researchers explained that they did not collect enough evidence to determine exactly the attack chain, the speculate the attackers used techniques similar to the ones employed in campaigns distributing the Kingminer, Lemon_Duck, or MyKings miners,

“The MrbMiner cryptojacking payload included a kernel-level device driver (WinRing0x64.sys), and a miner executable named Windows Update Service.exe to obfuscate its purpose. The executable was a modified version of the XMRig miner.” reads the post published by Sophos.

The malicious payload was designed to target Windows systems, but experts also found a Linux build of the miner on several servers they analyzed.

Sophos researchers discovered that cryptocurrency data was sent to wallets on the poolmrb.xyz and mrbpool.xyz domains as well as to the pool.supportxmr.com domain. The experts discovered that the cryptominer was downloaded from the vihansoft.ir, mrbfile, and mrbftp domains and communicated with the poolmrb/mrbpool domains.

The analysis of the configuration of the miner, the IP addresses involved in the campaign, and domains used by the threat actors led to a software company based in Iran.

“A lot of the records relating to the miner’s configuration, its domains and IP addresses, point to a single point of origin: a small software company based in Iran.” continues the analysis. “The payload location and the C2 server addresses are both hardcoded into the downloader. One domain, used as both a C2 and a payload server, was vihansoft.ir, registered to a software development company based in Iran. Payloads were also downloaded directly from the same IP address used to host vihansoft.ir (and from a few other domains which contained the string “mrb,” such as mrbfile.xyz).”

“We found the miner downloads in the web root of the vihansoft domain, in a repository under a now-shuttered Github user account, and on the mrbfile.xyz and mrbftp.xyz domains, as well as on a small number of IP addresses,” continues Sophos.

Experts noticed that the same username used for the GitHub account was present on the machine used to compile the miner. Despite it is not possible to retrieve any WHOIS information for both the “mrb” domains nor vihansoft, they use the same WHOIS privacy service, WhoisGuard, based in Panama, to conceal the domain ownership data.

If you want to receive the weekly Security Affairs Newsletter for free subscribe here.

[adrotate banner=”9″][adrotate banner=”12″]

Pierluigi Paganini

(SecurityAffairs – hacking, mrbminer)

[adrotate banner=”5″]

[adrotate banner=”13″]

Pierluigi Paganini

Pierluigi Paganini is member of the ENISA (European Union Agency for Network and Information Security) Threat Landscape Stakeholder Group and Cyber G7 Group, he is also a Security Evangelist, Security Analyst and Freelance Writer. Editor-in-Chief at "Cyber Defense Magazine", Pierluigi is a cyber security expert with over 20 years experience in the field, he is Certified Ethical Hacker at EC Council in London. The passion for writing and a strong belief that security is founded on sharing and awareness led Pierluigi to find the security blog "Security Affairs" recently named a Top National Security Resource for US. Pierluigi is a member of the "The Hacker News" team and he is a writer for some major publications in the field such as Cyber War Zone, ICTTF, Infosec Island, Infosec Institute, The Hacker News Magazine and for many other Security magazines. Author of the Books "The Deep Dark Web" and “Digital Virtual Currency and Bitcoin”.

Recent Posts

American fast-fashion firm Hot Topic hit by credential stuffing attacks

Hot Topic suffered credential stuffing attacks that exposed customers' personal information and partial payment data.…

3 hours ago

Cisco addressed high-severity flaws in IOS and IOS XE software

Cisco addressed multiple vulnerabilities in IOS and IOS XE software that can be exploited to…

17 hours ago

Google: China dominates government exploitation of zero-day vulnerabilities in 2023

Google's Threat Analysis Group (TAG) and Mandiant reported a surge in the number of actively…

24 hours ago

Google addressed 2 Chrome zero-days demonstrated at Pwn2Own 2024

Google addressed two zero-day vulnerabilities in the Chrome web browser that have been demonstrated during…

1 day ago

INC Ransom stole 3TB of data from the National Health Service (NHS) of Scotland

The INC Ransom extortion group hacked the National Health Service (NHS) of Scotland and is threatening…

2 days ago

CISA adds Microsoft SharePoint bug disclosed at Pwn2Own to its Known Exploited Vulnerabilities catalog

U.S. Cybersecurity and Infrastructure Security Agency (CISA) adds a Microsoft SharePoint vulnerability disclosed at the…

2 days ago

This website uses cookies.