attack-tree.md

Attack Tree Analysis for nuke-build/nuke

Objective: Compromise Application via Nuke Build Process

Attack Tree Visualization

• Compromise Application via Nuke Build Process [CRITICAL NODE]
  • Exploit Build Script Vulnerabilities [CRITICAL NODE] [HIGH-RISK PATH START]
    • Code Injection in Build Script [CRITICAL NODE] [HIGH-RISK PATH CONTINUES]
      • Inject Malicious Code via External Configuration [HIGH-RISK PATH CONTINUES]
        • Unsanitized Input from Environment Variables [HIGH-RISK PATH CONTINUES] [CRITICAL NODE]
        • Unsanitized Input from External Files (e.g., config files read by build script) [HIGH-RISK PATH CONTINUES]
    • Dependency Manipulation in Build Script [HIGH-RISK PATH START]
      • Introduce Malicious NuGet Packages [CRITICAL NODE] [HIGH-RISK PATH CONTINUES]
        • Dependency Confusion Attack (using public/private package feeds) [HIGH-RISK PATH CONTINUES] [CRITICAL NODE]
  • Exploit Build Environment Manipulation [CRITICAL NODE] [HIGH-RISK PATH START]
    • Compromise Build Server Environment [CRITICAL NODE] [HIGH-RISK PATH CONTINUES]
      • Gain Access to Build Server (e.g., weak credentials, unpatched server) [HIGH-RISK PATH CONTINUES] [CRITICAL NODE]
  • Exploit Exposed Sensitive Information in Build Process [CRITICAL NODE] [HIGH-RISK PATH START]
    • Secrets Hardcoded in Build Script (API keys, credentials) [HIGH-RISK PATH CONTINUES] [CRITICAL NODE]
  • Supply Chain Attacks via Nuke Dependencies [CRITICAL NODE]
    • Compromise NuGet Package Feed [CRITICAL NODE]

Attack Tree Path: High-Risk Path: Unsanitized Input -> Code Injection -> Exploit Build Script -> Compromise Application

• Critical Node: Unsanitized Input from Environment Variables:

  • Attack Vector: The Nuke build script reads environment variables without proper validation or sanitization. An attacker can control these environment variables (e.g., if they have access to the build server or CI/CD pipeline configuration) and inject malicious commands or code.
  • Likelihood: Medium-High. Environment variables are commonly used for configuration, and developers may overlook sanitization in build scripts.
  • Impact: High. Successful code injection can lead to complete compromise of the build process and potentially the deployed application.
  • Mitigation:
    • Input Validation and Sanitization: Thoroughly validate and sanitize all environment variables used in the build script. Use allow-lists and escape special characters.
    • Principle of Least Privilege: Run build processes with minimal necessary privileges to limit the impact of code injection.

• Critical Node: Unsanitized Input from External Files (e.g., config files read by build script):

  • Attack Vector: Similar to environment variables, if the build script reads external configuration files (e.g., JSON, YAML, INI) without proper validation, an attacker who can modify these files (e.g., through compromised storage or access control weaknesses) can inject malicious code or configuration.
  • Likelihood: Medium. External configuration files are common, and vulnerabilities can arise if parsing and usage are not secure.
  • Impact: High. Code injection or manipulation of build logic through configuration files can lead to application compromise.
  • Mitigation:
    • Input Validation and Sanitization: Validate and sanitize data read from external configuration files. Use secure parsing libraries and schema validation.
    • Secure File Storage and Access Control: Protect configuration files with appropriate access controls and ensure secure storage.

Attack Tree Path: High-Risk Path: Dependency Confusion -> Introduce Malicious NuGet Packages -> Dependency Manipulation -> Exploit Build Script -> Compromise Application

• Critical Node: Dependency Confusion Attack (using public/private package feeds):

  • Attack Vector: If the application uses both public (NuGet.org) and private NuGet feeds, an attacker can perform a dependency confusion attack. They upload a malicious package to the public NuGet.org with the same name as an internal, private package. When the build process attempts to resolve dependencies, it might mistakenly download the malicious public package instead of the intended private one.
  • Likelihood: Medium. Dependency confusion attacks are a known and increasingly common supply chain attack vector.
  • Impact: High. A malicious package introduced into the build process can inject backdoors, steal data, or disrupt the application.
  • Mitigation:
    • Prioritize Private Feeds: Configure NuGet to prioritize private feeds over public feeds.
    • Package Namespace Reservation: Reserve package namespaces on public registries to prevent attackers from using your internal package names.
    • Dependency Pinning/Locking: Use dependency pinning or locking to ensure consistent and predictable dependency versions, reducing the chance of unexpected malicious package inclusion.
    • Package Integrity Verification: Implement and enforce package integrity verification (e.g., using package signing and checksums).

• Critical Node: Introduce Malicious NuGet Packages:

  • Attack Vector: This is the broader category encompassing dependency confusion and other methods of introducing malicious NuGet packages into the build process. This could also include compromising a legitimate but less popular NuGet package that is a dependency.
  • Likelihood: Medium. Supply chain attacks are a growing threat, and NuGet packages are a potential target.
  • Impact: High. Malicious packages can have a wide range of negative impacts, from backdoors to data theft.
  • Mitigation:
    • Dependency Scanning: Regularly scan project dependencies for known vulnerabilities using tools like dotnet list package --vulnerable or dedicated SCA tools.
    • Software Composition Analysis (SCA): Implement SCA to analyze dependencies for security risks and license compliance.
    • Regular Dependency Audits: Periodically audit project dependencies and ensure they are from trusted sources.

Attack Tree Path: High-Risk Path: Gain Access to Build Server -> Compromise Build Server Environment -> Build Environment Manipulation -> Compromise Application

• Critical Node: Gain Access to Build Server (e.g., weak credentials, unpatched server):

  • Attack Vector: An attacker gains unauthorized access to the build server. This could be through various means, including:
    • Weak Credentials: Brute-forcing or guessing weak passwords for build server accounts.
    • Unpatched Server: Exploiting known vulnerabilities in the build server's operating system or software.
    • Misconfigurations: Exploiting misconfigurations in the build server's security settings.
  • Likelihood: Medium. Build servers, if not properly secured, can be vulnerable targets.
  • Impact: High. Compromising the build server grants the attacker significant control over the build process and potentially the entire application deployment pipeline.
  • Mitigation:
    • Strong Authentication: Enforce strong passwords, multi-factor authentication (MFA), and principle of least privilege for build server access.
    • Regular Security Patching: Keep the build server's operating system and software up-to-date with the latest security patches.
    • Server Hardening: Harden the build server by disabling unnecessary services, configuring firewalls, and implementing intrusion detection/prevention systems.
    • Security Monitoring: Implement security monitoring and logging on the build server to detect suspicious activity.

• Critical Node: Compromise Build Server Environment:

  • Attack Vector: Once an attacker has gained access to the build server, they can compromise the build environment. This includes:
    • Modifying Files: Altering build scripts, configuration files, or tools on the build server.
    • Manipulating Environment Variables: Setting malicious environment variables that affect the build process.
    • Installing Malicious Tools: Installing backdoors or malicious software on the build server.
  • Likelihood: Medium (if build server access is gained).
  • Impact: High. A compromised build environment can be used to inject malicious code into the application, steal sensitive data, or disrupt the build process.
  • Mitigation:
    • Immutable Build Environments (where feasible): Use containerized builds or other immutable infrastructure to reduce the risk of environment drift and manipulation.
    • Configuration Management: Use configuration management tools to ensure consistent and auditable build server configurations.
    • Regular Security Audits: Conduct regular security audits of the build server environment to detect unauthorized changes or vulnerabilities.

Attack Tree Path: High-Risk Path: Secrets Hardcoded in Build Script -> Exposed Sensitive Information -> Exploit Misconfigurations -> Compromise Application

• Critical Node: Secrets Hardcoded in Build Script (API keys, credentials):
  • Attack Vector: Developers mistakenly hardcode sensitive information like API keys, database credentials, or other secrets directly into the Nuke build script. This makes secrets easily discoverable if the build script is exposed (e.g., in version control, build logs, or if the build server is compromised).
  • Likelihood: Medium-High. Hardcoding secrets is a common developer mistake, especially in scripts or quick prototypes.
  • Impact: High. Exposed secrets can lead to the compromise of associated accounts, systems, and data.
  • Mitigation:
    • Secret Management Solutions: Use dedicated secret management solutions (e.g., Azure Key Vault, HashiCorp Vault, AWS Secrets Manager) to store and manage secrets securely.
    • Environment Variable Injection from Secure Stores: Inject secrets into the build process as environment variables from secure secret stores, rather than hardcoding them.
    • Secret Scanning Tools: Use automated secret scanning tools to detect accidentally hardcoded secrets in code repositories and build scripts.
    • Developer Training: Train developers on secure secret management practices and the risks of hardcoding secrets.