Container Supply Chain Attacks Cash In on Cryptojacking

Threats against cloud-native infrastructure are on the rise, particularly as attackers target cloud and container resources to power their illicit cryptomining operations. In the latest twist, cybercriminals are wreaking havoc on cloud resources to both propagate and run cryptojacking enterprises in costly schemes that cost victims some $50 in cloud resources for every $1 worth of cryptocurrency that the crooks mine off of these compute reserves.

That's according to a new report out today from Sysdig, which shows that while the bad guys will indiscriminately attack any weak cloud or container resources they can get their hands on to power money-making cryptomining schemes, they're also cleverly strategic about it. 

In fact, many of the most crafty software supply chain attacks are in large part designed to spawn cryptominers via infected container images. Attackers not only leverage source code dependencies most commonly thought of in offensive supply chain attacks — they also leverage malicious container images as an effective attack vehicle, according to Sysdig's "2022 Cloud-Native Threat Report." 

Cybercriminals are taking advantage of the trend within the development community to share code and open source projects via premade container images via container registries like Docker Hub. Container images have all the required software installed and configured in an easy-to-deploy workload. While that's a serious time saver for developers, it also opens up a path for attackers to create images that have malicious payloads built in and then to seed platforms like DockerHub with their malicious wares. All it takes is for a developer to run a Docker pull request from the platform to get that malicious image running. What's more, the Docker Hub download and installation is opaque, making it even harder to spot the potential for trouble.

"It’s clear that container images have become a real attack vector, rather than a theoretical risk," the report explained, for which the Sysdig Threat Research Team (TRT) went through a monthslong process of sifting through public container images uploaded by users worldwide onto DockerHub to find malicious instances. "The methods employed by malicious actors described by Sysdig TRT are specifically targeted at cloud and container workloads."

The team's hunt surfaced more than 1,600 malicious images containing cryptominers, backdoors, and other nasty malware disguised as legitimate popular software. Cryptominers were far and away the most prevalent, making up 36% of the samples.

"Security teams can no longer delude themselves with the idea that 'containers are too new or too ephemeral for threat actors to bother,'" says Stefano Chierici, senior security researcher at Sysdig and co-author of the report. "Attackers are in the cloud, and they are taking real money. The high prevalence of cryptojacking activity is attributable to the low risk and high reward for the perpetrators."

TeamTNT and Chimera

As a part of the report, Chierici and his colleagues also did a deep-dive technical analysis of the tactics, techniques, and procedures (TTPs) of the TeamTNT threat group. Active since 2019, the group according to some sources has compromised over 10,000 cloud and container devices during one of its most prevalent attack campaigns, Chimera. It's best known for cryptojacking worm activity and according to the report, TeamTNT continues to refine its scripts and its TTPs in 2022. For example, it now connects scripts with the AWS Cloud Metadata service to leverage credentials associated with an EC2 instance and gain access to other resources tied to a compromised instance.

"If there are excessive permissions associated with these credentials, the attacker could gain even more access. Sysdig TRT believes that TeamTNT would want to leverage these credentials, if capable, to create more EC2 instances so it could increase its cryptomining capabilities and profits," the report said.

As part of its analysis, the team dug into a a number of XMR wallets used by TeamTNT during mining campaigns to figure out the financial impact of cryptojacking. 

Utilizing technical analysis of the threat group's operational practices during the Chimera operation, Sysdig was able to find that the adversary cost its victims $11,000 on a single AWS EC2 instance for every XMR it mined. The wallets the team recovered amounted some 40 XMR, meaning that the attackers drove up a cloud bill of nearly $430,000 to mine those coins. 

Using coin valuation from earlier this year, the report estimated the value of those coins equals about $8,100, with back-of-envelope figuring then showing that for every dollar the bad guys make, they cost victims at least $53 in cloud bills alone.