Summary:
In June 2024, ESET researchers identified a new ransomware group, Embargo, utilizing a Rust-based toolkit for its operations. The toolkit consists of MDeployer, a loader, and MS4Killer, an EDR killer. Both tools are designed to facilitate the deployment and execution of the Embargo ransomware. MS4Killer is particularly noteworthy as it is custom-compiled for each victim's environment, targeting and evading specific security solutions utilizing techniques like Bring Your Own Vulnerable Driver (BYOVD). The group's choice of Rust for developing its ransomware demonstrates its sophistication and resourcefulness.

Embargo Ransomware has been observed by ESET targeting US companies since July 2024. The group's toolkit has been evolving, as evidenced by the discovery of multiple versions of MDeployer in a single intrusion. The group's tactics include the use of a double extortion method, where victims' data is exfiltrated and published online unless a ransom is paid. Additionally, based on Eset's findings, Embargo is suspected of operating as a ransomware-as-a-service (RaaS) provider, offering its services to affiliates. They operate utilizing a typical leak site.

Security Officer Comments:
The emergence of Embargo, a new ransomware group leveraging Rust-based tooling, highlights the ongoing evolution of ransomware threats. The group's ability to customize its toolkit and its focus on defense evasion techniques underscore its sophistication. The likelihood of them performing RaaS operations highlights their swift evolution caused by the strengthening of relationships within the cybercrime ecosystem. The use of Rust as the primary programming language for its tools further demonstrates the group's technical capabilities.

Organizations must remain vigilant against threats posed by emerging ransomware groups like Embargo. Implementing robust security measures, including endpoint protection, network security, and regular patching, is essential to mitigate the risk of ransomware attacks. Additionally, organizations should invest in employee training to raise awareness about ransomware threats and best practices for prevention.

Suggested Corrections:
IOCs and MITRE ATT&CK Techniques are published here.

Backup your data, system images, and configurations, regularly test them, and keep the backups offline: Ensure that backups are regularly tested and that they are not connected to the business network, as many ransomware variants try to find and encrypt or delete accessible backups. Maintaining current backups offline is critical because if your network data is encrypted with ransomware, your organization can restore systems.

Update and patch systems promptly: This includes maintaining the security of operating systems, applications, and firmware in a timely manner. Consider using a centralized patch management system; use a risk-based assessment strategy to drive your patch management program.

Test your incident response plan: There's nothing that shows the gaps in plans more than testing them. Run through some core questions and use those to build an incident response plan: Are you able to sustain business operations without access to certain systems? For how long? Would you turn off your manufacturing operations if business systems such as billing were offline?

Check Your Security Team's Work: Use a 3rd party pen tester to test the security of your systems and your ability to defend against a sophisticated attack. Many ransomware criminals are aggressive and sophisticated and will find the equivalent of unlocked doors.

Segment your networks: There's been a recent shift in ransomware attacks – from stealing data to disrupting operations. It's critically important that your corporate business functions and manufacturing/production operations are separated and that you carefully filter and limit internet access to operational networks, identify links between these networks, and develop workarounds or manual controls to ensure ICS networks can be isolated and continue operating if your corporate network is compromised. Regularly test contingency plans such as manual controls so that safety-critical functions can be maintained during a cyber incident.

Train employees: Email remains the most vulnerable attack vector for organizations. Users should be trained on how to avoid and spot phishing emails. Multi-factor authentication can help prevent malicious access to sensitive services.

Link(s):
https://www.welivesecurity.com/en/eset-research/embargo-ransomware-rocknrust/