Container Security

Container Security is the practice of protecting the entire lifecycle of containerized applications, from the initial build to runtime deployment. It involves multiple layers of defense, including scanning container images for vulnerabilities in software libraries and dependencies, securing the container registry where images are stored, and hardening the host operating system and orchestration platforms like Kubernetes. During runtime, container security focuses on monitoring for anomalous behavior, enforcing network segmentation, and ensuring containers operate with the principle of least privilege to minimize the potential impact of a breach within the dynamic, distributed environments common in modern cloud-native computing.

1. Introduction to Container Security
   1. Overview of Container Security
      1. Definition and Scope of Container Security
      2. Security Challenges in Containerized Environments
      3. Container Security vs Traditional Security Models
   2. Core Concepts of Containerization
      1. Definition and Purpose of Containers
      2. Containers vs Virtual Machines
         1. Architectural Differences
         2. Resource Isolation Mechanisms
         3. Performance Implications
         4. Security Trade-offs
      3. The Shared Kernel Architecture
         1. Linux Kernel Fundamentals
         2. Kernel Namespaces
            1. PID Namespaces
            2. Network Namespaces
            3. Mount Namespaces
            4. User Namespaces
            5. IPC Namespaces
            6. UTS Namespaces
         3. Control Groups (cgroups)
            1. Resource Limiting
            2. Resource Accounting
            3. Process Prioritization
            4. Memory Management
            5. CPU Management
            6. I/O Management
         4. Capabilities and Privileges
            1. Linux Capabilities Overview
            2. Capability Sets
            3. Dropping Unnecessary Capabilities
            4. Capability Inheritance
      4. Key Container Components
         1. Container Images
            1. Image Layers and Union Filesystems
            2. Image Metadata and Manifests
            3. Image Tagging and Versioning
            4. Image Repositories and Namespaces
         2. Container Registries
            1. Public Registries
            2. Private Registries
            3. Registry Architecture
            4. Registry APIs
         3. Container Runtimes
            1. Docker Engine
            2. containerd
            3. CRI-O
            4. OCI Runtime Specification
            5. Low-level vs High-level Runtimes
         4. Container Orchestrators
            1. Kubernetes Architecture
            2. Docker Swarm
            3. Container Scheduling
            4. Service Discovery
            5. Load Balancing
   3. The Container Attack Surface
      1. Host System Vulnerabilities
         1. Host OS Security Weaknesses
         2. Kernel Vulnerabilities
         3. Host Resource Exposure
         4. Privileged Container Risks
      2. Container Runtime Attack Vectors
         1. Daemon Privileges and Permissions
         2. API Exposure and Authentication
         3. Socket Security
         4. Runtime Configuration Vulnerabilities
      3. Orchestration Layer Threats
         1. Control Plane Security Risks
         2. Configuration Management Vulnerabilities
         3. API Server Exposure
         4. Cluster Communication Security
      4. Registry Security Risks
         1. Unauthorized Access Scenarios
         2. Malicious Image Distribution
         3. Registry Compromise
         4. Image Tampering
      5. Container Image Vulnerabilities
         1. Embedded Software Vulnerabilities
         2. Outdated Dependencies
         3. Malicious Code Injection
         4. Supply Chain Attacks
      6. Application-Level Threats
         1. Application Vulnerabilities in Containers
         2. Insecure Application Defaults
         3. Runtime Application Attacks
         4. Data Exposure Risks
   4. Fundamental Security Principles for Containers
      1. Defense in Depth
         1. Layered Security Controls
         2. Multiple Security Boundaries
         3. Redundancy and Failover Mechanisms
      2. Principle of Least Privilege
         1. User Privilege Management
         2. Process Capability Restrictions
         3. Resource Access Limitations
         4. Network Access Controls
      3. Immutability
         1. Immutable Infrastructure Concepts
         2. Container Immutability Benefits
         3. Configuration Management
         4. State Management Strategies
      4. Ephemerality
         1. Short-lived Container Benefits
         2. Reducing Attack Windows
         3. Stateless Application Design
         4. Container Lifecycle Management