We are excited to announce support for a new detection type: identification of malicious port scans.

Port scanners are applications that probe a host or server to find open ports or “weak points” in your network. These can be used by malicious actors to exploit vulnerabilities and identify network or security services running on a host.

Port Scanning
There are a variety of TCP ports, numbered from 0 to 65535, with the standard ports occupying numbers 0 to 1023. A standard port that is left open can indicate an infected or vulnerable port. 

Commonly used ports include:

• Port 20 (UDP): File Transfer Protocol (FTP) for data transfer
• Port 22 (TCP): Secure Shell (SSH) protocol for secure logins, FTP, and port forwarding
• Port 23 (TCP): Telnet protocol for unencrypted text commutations
• Port 53 (UDP): Domain Name System (DNS) translates names of all computers on internet-to-IP addresses
• Port 80 (TCP): World Wide Web HTTP

Port scans are not always malicious – they can also occur when security services are deployed on virtual machines in your environment. This occurs because the services  conduct port scans to alert you to potentially misconfigured ports that have been left open. 

Indicators of Compromise

Potentially malicious port scans are detected through their suspicious access patterns – including repeated attempts to connect to multiple ports over a short period of time, or connecting a resource or host to multiple ports over a short period of time. A port scan attack aims to locate open ports to discover which services the machine is running and to identify its operating system, to inform which vulnerabilities to exploit.

A port scan can provide useful information about a network environment, including: 

• Existing network defenses, such as firewalls
• Running applications
• Machines that are online
• Information about the targeted system
• Information about vulnerable networks and servers

Attackers can then use this information to conduct an attack on a virtual machine.

Port Scan Attack Methods

In a port scanning attack, attackers generally do one of the following:

1. Leverage a resource to perform outbound port scans to a remote host
2. Use a remote host to port scan a resource 
3. Use an internal source to port scan a resource 
4. Leverage a remote host using UDP to port scan a resource 

Upwind leverages runtime data to rapidly identify unusual port scanning and immediately alert you to suspicious activity. Read more about port scanning detections in the Upwind Documentation Center.

We are excited to announce a new threat detection, with the ability to identify an exposed Kubernetes Dashboard.

This threat detection will inform you when the Kubernetes dashboard for your cluster is exposed to the internet by a Load Balancer.  Exposing your dashboard to the internet makes the management interface of your cluster vulnerable to attack. This creates an opportunity for adversaries to exploit weaknesses in authentication and access control, compromising the security of your system.

What is the Kubernetes Dashboard?

The Kubernetes Dashboard is a web-based Kubernetes user interface (UI) that is used to manage a Kubernetes system, allowing you to run commands on pods within the dashboard and deploy access keys to your clusters.

The Kubernetes Dashboard has a number of uses, including:

• Deploying containerized applications to the Kubernetes cluster
• Troubleshooting your containerized application
• Managing cluster resources
• Getting on overview of applications running on the cluster
• Creating or modifying Kubernetes resources such as DaemonSets or Deployments

The Kubernetes Dashboard also gives you information on the state of Kubernetes resources in your cluster and notifies you or any potential errors.

Indicators of Compromise

While the Kubernetes Dashboard gives you extensive capabilities for managing Kubernetes, it can also be a launchpad for attacks if there are misconfigurations or excessive/loose permissions. A Load Balancer can expose your Kubernetes Dashboard to the Internet if not properly configured, ultimately making the management interface of your cluster vulnerable. This can also create an opportunity for attackers to exploit any weaknesses in authentication and access control, such as overly permissive RBAC, which can potentially compromise the security of your system.

Use Upwind’s Exposed Kubernetes Dashboard Detection to identify any exposures of your Kubernetes Dashboard and proactively remediate exposures or open attack paths. For  more information on the Exposed Kubernetes Dashboard detection, please visit the Upwind Documentation Center (login required).

We are excited to announce the release of a new threat detection type – exec command in a kube-system namespace.

This detection alerts you that kubectl exec has run a command in your environment in the kube-system namespace, which may indicate a suspicious activity. 

What is Kubectl Exec?

Kubectl is a command line tool used to communicate with Kubernetes clusters via the Kubernetes API. This is an admin tool for Kubernetes clusters that can be used to monitor Kubernetes status, manage and edit resources. 

Kubectl exec gives you full shell access to the container, meaning you can execute commands inside a container directly from kubectl. Before you use kubectl exec to execute a command in a container, you need to know the container namespaces in the cluster. kubectl exec is a powerful tool, it is primarily used for inspecting containers and viewing containers’ status and contents.

Indicators of Compromise

While kubectl exec is used for improving container monitoring and performance, it can also be used by bad actors even if one token of your kubernetes has gotten into the wrong hands. 

One sign of compromise can be if kubectl exec is used to execute a command in the kube-system namespace. The kube-system namespace is a default namespace that is used mostly for system-level components like kube-dns and kube-proxy. It is very unusual to execute commands inside pods or containers in the kube-system namespace because they should be immutable at runtime and acquire high permissions by default and have access to secrets and control-plane resources.

A kube-system attack often includes:

1. An attacker uses kubectl exec in the kube-system namespace, which has high permissions by default
2. The attacker then uses kubectl exec to run the exec command in a pod and establish a temporary shell session
3. Using kubectl exec and a temporary shell session then gives the attacker the ability to execute any process or command in the pod. 
4. The attacker then uses the interactive shell to run commands and gain access into the pod’s data, including permissions and secrets. 

Upwind leverages runtime data to rapidly identify unusual kubectl exec commands run in the kube-system namespace and immediately alert you to suspicious activity. Read more about Kubectl Exec detections in the Upwind Documentation Center.

We are excited to announce the release of a new threat detection type – Spambot detection that targets suspicious activity on Port 25.

A Spambot detection alerts you that a resource in your environment is abnormally communicating with a remote host most commonly via port 25.

What is SMTP?

Simple Mail Transfer Protocol (SMTP) is an email protocol and one of multiple internet protocols that use plaintext, meaning that the communication is easy to see and read. When sending plaintext, SMTP uses port 25. Many firewalls and end-user networks block port 25, since spammers try to abuse it and send large amounts of spam.

Indicators of Compromise

There are several ways that SMTP can be used for malicious purposes, including phishing and spam emails, as well as being used by an attacker in reconnaissance when preparing for an attack.

Upwind’s Spambot detection informs you that a resource within your environment is abnormally communicating with a remote host on port 25, with no prior history of communications on port 25 between this resource and host. This behavior could indicate that a malicious actor has accessed a workload and executed a spambot leading to abnormal SMTP traffic.

There are several kinds of common Spambot attacks, including:

1. Spam and phishing emails: an attacker compromises an organization’s mail server and sends phishing emails from a compromised account. 
2. Emailing malwares: while less common in recent years, mass-mailer malware worms have historically been sent to distribute malware through email when opened by the recipient.
3. Credential stealing: an attacker discovers email addresses and sends spam to try to gain their credentials to online services. Attackers can also use SMTP with a VRFY command to validate email addresses.

Spambot attacks are common, and they can pose a significant danger to organizations if an attacker is able to gain access to a workload and execute a spambot, potentially leading to attacks such as those listed above, or to carrying out reconnaissance ahead of a larger planned attack on your infrastructure or network.

Upwind leverages runtime data to rapidly identify unusual port 25 communication and immediately alert you to suspicious activity. Read more about Spambot detections in the Upwind Documentation Center.