Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Cloud Security //

IaaS

3/26/2018
09:35 AM
Larry Loeb
Larry Loeb
Larry Loeb
50%
50%

Cybercriminals Using Kubernetes, Docker to Bitcoin Mine

Supposedly safe and secure Docker containers and the Kubernetes orchestration system can actually be manipulated to mine Bitcoin and other cryptocurrencies, researchers have found.

Cybercriminals have been running cryptocurrency attacks on hijacked machines for some time, finding it more profitable than ransomware. Now however, malware authors have found a new way to take their nefarious actions into the cloud and bypass the need for hijacking individual computers.

Reports have surfaced of attempts to run mining activities on Docker and Kubernetes systems. At the start of 2018, Sysdig researchers found that the Kubernetes instances on their honeypot servers were being attacked, with the aim of creating Docker containers that would mine Bitcoin.

Sysdig saw that the attacker created a container that mounted /etc/ from the host filesystem to /mnt/etc/ inside the container.

Then, by writing to files below /mnt/etc/ inside the container, they can write to files below /etc on the host. They were writing to /etc/crontab, which then downloaded a file every minute and then ran as a bash script. That script would kill any competing mining programs and install its own Bitcoin miner which used all of the host machine's available cores.

A similar attack scheme was noted by Aqua Security and explained on its blog. The effective difference between the two events was Aqua noted Monero mining occurring on net-exposed Docker containers that were not bounded by Kubernetes.

The unanswered question in all of this was how a Kubernetes instance -- such as Sysdig had running -- could be breached to allow the mining to happen.

It took Alexander Urcioli, senior security engineer at Handy HQ, to connect the dots.

Urcioli discovered that on a co-worker's machine an attacker ran commands on a Kubernetes instance without authentication, something that should not have happened. He wrote on Medium that he discovered a misconfiguration in how Kubernetes was deployed that had startling effects.


The fundamentals of network security are being redefined -- don't get left in the dark by a DDoS attack! Join us in Austin from May 14-16 at the fifth annual Big Communications Event. There's still time to register and communications service providers get in free!

Specifically, Urcioli knew the Kubernetes api-server was publicly exposed to the Internet but was protected with certificate authentication. He realized that:

Unless you specify some flags on Kubelet, it's default mode of operation is to accept unauthenticated API requests. Keep in mind that in order for master -> node communication to work, the Kubernetes API server must be able to talk to kubelet on your nodes.

The co-worker's server had mistakenly been configured to allow the public exposing of the kubelet ports (tcp 10250, tcp 10255) to the net. That meant the attacker could access them as use the kubelet API as a backdoor into the cluster.

And now the reason the attack worked at all seems far less mysterious. The kubelet has to be locked down, or it will let almost anything get in. This has to be done explicitly, because it doesn't happen by default.

Configuration issues are being realized as a major security issue of late. Recent configuration problems in Amazon S3 containers have left private information publicly accessible, for example. Security professionals will need to pay attention to the details of configuration or pay the price in Monero.

Related posts:

— Larry Loeb has written for many of the last century's major "dead tree" computer magazines, having been, among other things, a consulting editor for BYTE magazine and senior editor for the launch of WebWeek.

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
Manchester United Suffers Cyberattack
Dark Reading Staff 11/23/2020
As 'Anywhere Work' Evolves, Security Will Be Key Challenge
Robert Lemos, Contributing Writer,  11/23/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Write a Caption, Win an Amazon Gift Card! Click Here
Latest Comment: He hits the gong anytime he sees someone click on an email link.
Current Issue
2021 Top Enterprise IT Trends
We've identified the key trends that are poised to impact the IT landscape in 2021. Find out why they're important and how they will affect you today!
Flash Poll
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-29129
PUBLISHED: 2020-11-26
ncsi.c in libslirp through 4.3.1 has a buffer over-read because it tries to read a certain amount of header data even if that exceeds the total packet length.
CVE-2020-29130
PUBLISHED: 2020-11-26
slirp.c in libslirp through 4.3.1 has a buffer over-read because it tries to read a certain amount of header data even if that exceeds the total packet length.
CVE-2020-26936
PUBLISHED: 2020-11-26
Cloudera Data Engineering (CDE) before 1.1 was vulnerable to a CSRF attack.
CVE-2020-29042
PUBLISHED: 2020-11-26
An issue was discovered in BigBlueButton through 2.2.29. A brute-force attack may occur because an unlimited number of codes can be entered for a meeting that is protected by an access code.
CVE-2020-29043
PUBLISHED: 2020-11-26
An issue was discovered in BigBlueButton through 2.2.29. When at attacker is able to view an account_activations/edit?token= URI, the attacker can create an approved user account associated with an email address that has an arbitrary domain name.