What is Container Runtime Security?

Container runtime security protects your applications during their most vulnerable phase. This post reveals five critical threats that can compromise your environment and offer practical strategies.
By SentinelOne October 2, 2024

Most security teams have one common and ongoing challenge –  securing containerized applications during runtime. Your containers are the most vulnerable to attacks like privilege escalations and zero-day exploits during this phase. In fact, a recent study found that 85% of organizations using containers experienced cybersecurity incidents in 2023, with 32% of these incidents occurring during runtime.

So what happens if there is a single oversight? You endure significant breaches, operational disruptions, and downtime – an outcome you definitely do not want for your organization. In this post, we provide actionable insights, threats, and proven strategies to improve your container runtime security.

What Is Container Runtime Security?

Container runtime security is the practice of protecting containers while they are actively running in a production environment. It involves real-time monitoring and threat detection to identify and mitigate vulnerabilities that can arise during execution. It works to prevent malicious activities, unauthorized access, and misconfigurations of systems by continuously monitoring container behavior and enforcing appropriate security policies.

Importance of Container Runtime Security

Containers are most vulnerable when they are running. Unlike static analysis or pre-deployment checks, runtime security addresses real-time threats that can exploit weaknesses as containers execute. Container runtime protection ensures the integrity of your applications, supports and maintains compliance, and secures sensitive data.

The Hidden Costs of Failing to Secure Your Container Runtime

Container runtime security is not an option, it is sine qua non – indispensable for your organization. Failing to understand its significance can be heavy on your pockets. We have listed a few for you:

  • Data breaches: Most containers have sensitive and classified information – usually from your clients. Any laxity in preserving the integrity of this data can be seen as a breach of confidence and drastically affect your reputation. So, you lose the data, and your credibility, and may have to battle out several expensive lawsuits.
  • Operational downtime: Your organization’s success banks on it working like a well-oiled machine. A security breach is like a wrench in your plans – forcing your entire operation to take an unwanted and costly break. One single security incident can impair your productivity and profitability.
  • Loss of Intellectual Property: Your containers also house valuable internal data such as proprietary algorithms, trade secrets, and unique codes. If attackers gain access to this data, you might have to completely discontinue certain products and services. Worst case scenario – your competition gets their hand on your IP; you might lose your competitive edge in the market and your clientele.
  • Increased insurance premiums: Did you know that businesses insure their cybersecurity? They do this mainly for two reasons – as an investment and to pay for expenses caused due to security breaches. However, if there is a security incident, you are looking at a higher rate of premium. Based on the severity of the breach and how you handle the remediation, you can face a complete denial of coverage.
  • High remediation costs: Fixing the container post-breach is another money (black) hole – and you also have to divert a good chunk of your resources to get everything up and running again. In order to repair the damage, you need to patch vulnerabilities, update configurations, and recover compromised systems. But that is not all. You also need to work diligently towards rebuilding the trust of your clients. You can do this by re-auditing your security protocols and improving them. And all these remedies are not cheap.
  • Compliance issues: Financial and healthcare services have an added expense – the fines levied on them for compromising sensitive client information and non-compliance. Moreover, they experience increased scrutiny from the regulatory bodies.

How Does Container Runtime Security Work?

Container runtime security works on a perpetual loop; supervising and analyzing containers’ behavior, throughout the entire execution. It has several key components:

  1. Real-time threat detection: One of the basic, but extremely significant capabilities of runtime security is detecting threats as they happen. It uses advanced security tools to keep a close watch on container activities. It also looks for suspicious behavior such as unauthorized system calls, unusual network connections, or attempts at privilege escalations. If a container tries to get hold of a file beyond its access or tries to connect with an external IP address, the system immediately red-flags it. Alerting security teams at the earliest allows for better damage control.
  2. Policy enforcement: Container runtime security is more than monitoring a container; it also helps in defining what a container can do through a set of rules and policies. These predefined boundaries regulate a container’s access to resources, networks, databases, and more. It also oversees communications between containers; and blocks them from deviating from the set rules.
  3. Incident response: Once the runtime security detects a threat in the container, it immediately takes steps such as isolating the affected container and warning the security teams. It also logs the incident information for forensic analysis and future improvements. It is important to note here that human intervention is required to mitigate the threat.
  4. Continuous monitoring: As runtime security monitors the containers continually, it helps maintain hygiene in the process and get real-time insight into the container’s health.

5 Critical Container Runtime Security Threats Every Enterprise Should Be Aware Of

Here are five critical container runtime security threats that every enterprise must know about:

#1. Configuration Drift

Did you know that Tesla’s Kubernetes Console Breach in 2018 was caused due to configuration drift? Its Kubernetes console was left exposed without password protection, allowing attackers to mine cryptocurrency. These configuration drifts happen when there is a disparity in the expected state due to unnoticed or unauthorized modifications. In the long run, this leads to new risks, compromised security, and gaps that are capable of being targeted by hackers.

#2. Malicious Code Execution

Containers are at their most vulnerable state during runtime, and attackers wait for this opportunity to stealthily inject malicious scripts or applications. Hilton Hotels had first-hand experience with this threat in 2020 when hackers exploited their docker container gaining access to guest data. To make matters worse, they later triggered a ransomware attack.

#3. Malware in Container Images

Container images are the foundational blocks on which a container is built. However, if these images are obtained from unvetted sources, there is a good chance that they are riddled with malware. Are you aware of the Docker Hub Malware Incident of 2019? Hundreds of malicious images with crypto miners were hosted on Docker. Since the discovery, Docker has tightened its security to avoid such breaches.

#4. Privilege Escalation Attacks

In a container, users are given proper authority to access information. But imagine if an attacker or hacker gets these privileges.  They could potentially use an organization’s resources, plant Malware, and disrupt business operations. No one in the cybersecurity world can forget the CVE-2019-5736 runs Vulnerability through which attackers gained root access to the host. They exploited the flaw to overwrite the host’s binary.

#5. Kernel Exploits

Host machines and containers often share the kernel, which invariably makes both susceptible to kernel exploits. Quite recently,  a critical Linux kernel vulnerability was discovered. Attackers gained access to overwrite files on read-only mounted containers. To stay ahead of such incidents, you need to regularly update and patch the kernel, along with implementing docker runtime security tools.

How to Detect and Remediate Runtime Risks in Your Environment?

The best way to maintain your application security is to detect and remediate runtime risks in a containerized environment. However, you need a systematic approach to this. So here is a step-by-step guide to help you effectively detect and resolve these risks.

Detection of Runtime Risks

  • Continuous real-time monitoring: Your first step towards achieving optimum container runtime security is to get tools that can monitor runtime activities in real time. These tools can monitor the event streams, track changes in resource usage and identify anomalies in container operations.

Pro-tip: Remember to configure the tools to send you an alert as soon as they detect privilege escalation or unauthorized system calls. These alarms allow you to expedite threat mitigation.

  • Behavioral analytics: The next step is to define a baseline for what you consider normal container activity. Once the system learns the usual pattern of container behavior – such as resource consumption, networking, activity, and so on – it can pinpoint the deviation. Behavioral analytics is probably the most beneficial tool when it comes to sophisticated threats (insider attacks).

Pro-tip: Standard signature-based methods are not always great at identifying advanced and subtle threats.

  • Snapshot scanning: Snapshot scan refers to taking a snapshot of various stages of container runtime. It can detect weaknesses such as misconfiguration or outdated software components, not identified during initial deployment.

Pro-tip: If your containers are constantly updated with new libraries or dependencies, snapshot scanning is a must-have step in your container runtime security routine.

  • System call monitoring: Container processes often make requests to the host system kernel. These ‘syscalls’ help the container interact with the operating system to access files or manage memory.  Your next step is to implement a system that can regularly monitor such calls and filter suspicious calls.

Pro-tip: Make sure to set up filters for setuid or setgid calls that can potentially change user or group ID.

  • Intrusion detection systems (IDS): The last step in detecting runtime risks is deploying container-specific IDS solutions to monitor network traffic, file integrity, and process activities within containers to detect potential intrusions.

Pro-tip: You can configure IDS to detect unauthorized access, data exfiltration attempts, or suspicious communications between containers.

Remediation of Runtime Risks

Once you’ve detected the runtime risks, it is time to respond to these threats and minimize their impact on your operations. Let’s take a look at some of the ways remediation can be managed:

  • Automated incident response: Upon detecting a threat, automate the response to minimize damage. This involves isolating or terminating compromised containers or rolling back to previous versions. So if the container is compromised, the system can automatically revert to a backup image or trigger an update of a secure version of the container.
  • Configuration management: We know that unmanaged configuration can result in a drift. You can avoid this by regularly reviewing and updating configurations. This ensures that the containers are not running with excessive privileges, unnecessary network access, or misconfigured storage volumes.
  • Access controls: Implement strict access controls using role-based access control (RBAC). You can define clear roles for users and processes, with precise permissions limiting what they can do within the containerized environment. By limiting access to critical components, you reduce the risk of an attacker gaining control of sensitive resources if a container is compromised.
  • Integration with security solutions: Ensure that your runtime security tools integrate seamlessly with other security solutions within your tech stack. ink container security tools with SIEM (Security Information and Event Management) systems or your cloud security platform to correlate alerts, identify wider attack patterns, and maintain end-to-end visibility of your infrastructure.
  • Continuous vulnerability scanning: Perform container runtime scanning regularly for known vulnerabilities and malware during runtime. Use tools that automatically scan containers for known CVEs (Common Vulnerabilities and Exposures), flagging outdated or vulnerable components.

Best Practices for Container Runtime Security

Container runtime security is essential for maintaining the integrity and confidentiality of containerized applications. You can strengthen the security by applying the following best practices:

#1. Use Minimal Base Images

Smaller images mean smaller attack surfaces; threat actors usually do not fret with these. Their small size also means that they only have the essential components, making them easier to manage, thereby also reducing the potential entry points for attackers.

#2. Regularly Update and Patch

Like any other software, containers also need to be regularly updated with newer patches to address vulnerabilities. The Heartbleed attack happened because a Docker image had an outdated version of OpenSSL. Integrate regular vulnerability scanning into your CI/CD pipeline to identify and address issues promptly.

#3. Implement Least Privilege

Attackers are always looking for entry points through available privileges. If instead of allowing your containers to run with root privileges, you set them up with lower-level permissions, you can easily avert a security risk.

#4. Leverage Security Modules

For added layers of security, choose security modules like Seccomp and AppArmor that can restrict the system calls that containers are allowed to make. These modules basically lock down kernel interactions and block unauthorized system calls, preventing container escape. They can also enforce stricter security policies, ensuring that containers operate within defined parameters and cannot perform unauthorized actions.

#5. Enable SELinux

Security-enhanced Linux (SELinux) is a reliable security mechanism that enforces mandatory access controls (MAC) on container processes. With SELinux, you can control and restrict a compromised container from accessing sensitive resources (configuration files, system libraries) on the host.

#6. Isolate Containers

Use network policies, firewalls, and other isolation techniques to separate containers from each other. This isolation limits the potential for lateral movement within your environment and reduces the risk of spreading compromises between containers.

#7. Monitor and Log activity

Implement tools that provide visibility into container runtime activities, such as process execution, network communications, and system calls. By logging and analyzing this data, you can identify suspicious behavior and respond to threats before they escalate.

#8. Use Trusted Registries

Using images from reputable sources reduces the risk of introducing malicious code into your environment. Additionally, ensure that images are signed and their integrity is verified before deployment to prevent tampering.

#9. Limit Resource Usage

Setting resource limits on containers is a key strategy for preventing denial-of-service (DoS) attacks and ensuring fair resource allocation. By capping CPU, memory, and storage usage, you can prevent any single container from overwhelming the host system and disrupting other applications.

#10. Conduct Regular Security Audits

Regular security audits and penetration testing should cover all aspects of container security, from image creation and configuration management to container runtime protection.

SentinelOne: Comprehensive Container Runtime Security

SentinelOne’s Singularity Cloud Workload Security (CWS) provides comprehensive protection for containerized workloads, focusing on real-time security during the runtime phase. The platform ensures your containers are protected against several threats through the following features:

  1. AI-powered real-time threat detection: SentinelOne’s CWS delivers real-time cloud workload protection platform (CWPP) capabilities that protect containerized environments from advanced threats like ransomware and zero-day exploits.
  2. Autonomous response and recovery: SentinelOne’s quick response capabilities ensure that when threats are detected, they are automatically neutralized to minimize downtime and ensure continuous availability. Its automated Storyline™ attack visualization maps to the MITRE ATT&CK TTP and also simplifies forensic artifact collection at scale.
  3. Comprehensive visibility and forensics: Through integration with the Singularity data lake, SentinelOne offers detailed forensic history and workload telemetry so security teams can investigate incidents thoroughly. The Workload Flight Data Recorder™ captures and records all relevant data for comprehensive visibility.
  4. Broad platform support and scalability: SentinelOne supports 14 major Linux distributions, multiple container runtimes (Docker, containers, cri-o), and both managed and self-managed Kubernetes services from leading cloud providers like Amazon Web Services (AWS), Microsoft Azure, and Google Cloud. It also integrates with Snyk and combines an agentless CNAPP with a unique offensive engine.
  5. eBPF architecture for stability and performance: The use of extended Berkeley packet filter (eBPF) architecture enhances the platform’s stability and performance. This design avoids kernel dependencies, resulting in low CPU and memory overhead.
  6. Integration with DevSecOps tools: SentinelOne integrates with DeSecOps tools for a seamless experience and continuous security monitoring throughout the development lifecycle.

Book a demo for SentinelOne to protect your container environments from threats.

FAQs

1. What is the runtime security of containers?

Runtime container security involves protecting containers while they are actively running. It focuses on detecting and mitigating threats such as unauthorized access, malware, and vulnerabilities during the container’s execution phase.

2. Who is responsible for container runtime security?

Container runtime security is typically the responsibility of the DevOps and security teams within an organization. They ensure security policies, monitoring, and response measures are in place to protect running containers.

3. Which tool is used for container security?

One of the best tools you can get for container security is SentinelOne. It comes with features like real-time threat detection, policy enforcement, and automated incident response, offering extensive security for your

4. What does container runtime mean?

A container runtime refers to the software that manages the container’s lifecycle, from creating, starting, and stopping, to deleting them.

5. How do you manage container security?

There are several practices that help you manage container security, such as regular vulnerability scanning, implementing least privilege, and monitoring runtime activities. You must also use other security tools for continuous protection.

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