Container Security Guide: Methodology, Tools, and Best Practices

Think of containers as magical boxes for software, holding everything it needs code, settings, and dependencies, ready to go anywhere seamlessly. This portability makes containers a game-changer, driving rapid adoption for streamlined development and deployment.

Containers have surged in popularity, with over 90% of organizations already using or planning to adopt them. However, this rise in adoption brings cyber security risks like misconfigurations and vulnerabilities, potentially leading to data breaches. Effective container security requires collaboration between development, operations, and security teams, aligning with cyber security principles.

In 2019, Docker Hub experienced a security breach, emphasizing the significance of container security. Hackers gained unauthorized access to a Docker Hub database, compromising sensitive data, including usernames and hashed passwords for approximately 190,000 accounts. This incident underscored the importance of securing container registries and implementing robust authentication mechanisms for effective vulnerability management in containerized environments.

Container Testing Metholodogy in Vulnerability Management

Reconnaissance

Adversaries employ various techniques to conduct discoveries and gather intelligence about the system and internal network. This reconnaissance phase allows attackers to understand the environment, assess potential targets, and determine how to proceed with their objectives. Common techniques for discovery in container environments include scanning for exposed services and ports within containers, enumerating running processes and services, querying container orchestrators for information about deployed containers and services, and inspecting container configurations and metadata to identify potential security vulnerabilities or misconfigurations.

Initial access

In this tactic adversary first breach a network's defenses. They do this through tactics like exploiting security vulnerabilities in publicly accessible web servers or misconfigurations in services. Once inside, they may continue access using legitimate accounts or external remote services. However, this access could be short-lived if passwords change, or they rely on default accounts. Tactics here include using web exploits, exploiting remote services, using valid accounts, or exploiting default ones.

Execution

Within container environments encompasses tactics that enable adversaries to execute code under their control on either local or remote systems. This code execution, typically malicious in nature, is often combined with tactics from other phases to accomplish broader objectives, such as network exploration or data exfiltration.

Persistence

In containerized environments, adversaries employ various techniques to ensure persistence, allowing them to maintain unauthorized access despite restarts or interruptions. These techniques include backdooring base images, exploiting vulnerabilities for container breakout, tampering with the filesystem to add malicious code or scripts, injecting malicious environment variables, and setting up covert network connections or persistent volume mounts. Attackers may also abuse misconfigurations in container orchestrators, create malicious cron jobs, or exploit runtime vulnerabilities.

Privilege Escalation

Adversaries seek to escalate their privileges to gain higher-level permissions within containers, enabling them to execute more sophisticated attacks. Despite the isolated nature of containers, attackers exploit vulnerabilities, misconfigurations, or weaknesses to elevate their privileges. Common techniques for privilege escalation in containers include exploiting vulnerabilities in container runtimes or orchestrators, abusing misconfigured security settings, leveraging container breakout vulnerabilities to access the underlying host, and manipulating container resources for elevated privileges.

Credential Access

Adversaries employ techniques like keylogging or credential dumping to steal sensitive account information such as usernames and passwords. By compromising legitimate credentials, attackers gain unauthorized access to systems, making their activities harder to detect and potentially enabling the creation of additional accounts. Leveraging these credentials allows adversaries to blend in with legitimate user activity, evade detection mechanisms, and escalate their privileges within container ecosystems.

Discovery

In the aftermath of a successful breach in containerized environments, adversaries embark on a critical phase known as post-exploitation discovery. This stage allows them to delve deeper into the compromised system and internal network, gathering crucial intelligence to advance their objectives. Techniques employed include enumerating running containers and services, querying container orchestration platforms, analyzing configuration files, exploring persistent storage, scanning for security vulnerabilities, intercepting network traffic, and exploiting container metadata APIs. Through meticulous post-exploitation discovery, adversaries gain a comprehensive understanding of the compromised environment, paving the way for more targeted and effective exploitation efforts.

Lateral movement

Presents a critical phase for adversaries seeking to extend their control within the network. After initial access, attackers navigate the container ecosystem, aiming to infiltrate remote systems and advance towards their target objectives. Techniques include container hopping within the same host or across clusters, compromising service accounts, orchestrator abuse, and manipulating inter-container communication. By executing these lateral movement tactics, attackers seek to escalate privileges, expand their reach, and maximize their impact within the containerized infrastructure.
 

Container Security Best Practices in Vulnerability Management

1. Regular Patching and Updates: Maintain up-to-date host OS and container runtime software to mitigate security vulnerabilities promptly.

2. Implement Network Segmentation: Divide network traffic to contain breaches and restrict unauthorized access within container environments.

3. Use of Minimal Host OS: Opt for streamlined host OS configurations to minimize attack surfaces and enhance security in container deployments.

4. Container Image Scanning: Employ automated scanning tools to detect security vulnerabilities in container images before deployment, ensuring a secure container environment.

5. Implement Access Controls: Enforce strict access controls, including role-based access and least privilege principles, to prevent unauthorized activities within containerized systems.

Container Security Automated Tools for Vulnerability Management

• Clair - Vulnerability Static Analysis for containers.
• Anchore - Open-source project for deep analysis of docker images.
• Falco - Falco, the cloud-native runtime security project, is the de facto Kubernetes threat detection engine. engine
• Harbor - Harbor is an open-source registry that secures artifacts with policies and role-based access control, ensures images are scanned and free from security vulnerabilities, and signs images as trusted.
• Trivy - Trivy is a simple and comprehensive vulnerability/misconfiguration scanner for containers and other artifacts..

Conclusion

While adopting containerization, prioritize security throughout the journey. While containers offer agility and scalability, they also introduce unique cyber security challenges. By integrating security into every aspect of your container strategy, you can harness the benefits of containerization while safeguarding your digital assets effectively. So, make security a priority by embracing containers and ensuring the integrity and resilience of deployments.