threat-modeling.md

Threat Model Analysis for microsoft/vcpkg

Threat: Dependency Confusion Attack

• Description: An attacker publishes a malicious package to a public registry (e.g., GitHub's default vcpkg registry) with the same name as a private package used internally. The attacker crafts the malicious package to have a higher version number. vcpkg, during dependency resolution, prioritizes the higher version, pulling the malicious package from the public registry instead of the intended private package.
  • Impact:
    • Execution of arbitrary code on developer machines or build servers.
    • Data exfiltration (source code, credentials, etc.).
    • Compromise of the application.
    • Potential lateral movement.
  • Affected vcpkg Component:
    • vcpkg install command and its dependency resolution logic.
    • Interaction with configured registries (especially the default public registry).
    • Manifest mode (vcpkg.json) dependency resolution.
  • Risk Severity: Critical
  • Mitigation Strategies:
    • Use a Private Registry: Host all dependencies, especially those with internal names, on a private vcpkg registry. Configure vcpkg to only use this private registry.
    • Namespace Packages: If using a public registry, use a unique namespace/prefix for all internal package names.
    • Version Pinning: Specify the exact version of every dependency in vcpkg.json.
    • Binary Caching: Use a secure binary caching solution.

Threat: Typosquatting Attack

• Description: An attacker publishes a malicious package with a name very similar to a popular, legitimate vcpkg package. A developer makes a typo when specifying the dependency, accidentally installing the malicious package.
  • Impact:
    • Execution of arbitrary code.
    • Data exfiltration.
    • Application compromise.
  • Affected vcpkg Component:
    • vcpkg install command.
    • Manifest mode (vcpkg.json) dependency resolution.
    • Interaction with configured registries.
  • Risk Severity: High
  • Mitigation Strategies:
    • Careful Dependency Specification: Double-check package names for typos.
    • Code Review: Review changes to vcpkg.json, paying attention to dependency names.
    • Use a Private Registry: Reduces the risk, as only approved packages are available.
    • Automated Dependency Analysis: Use tools that can detect potential typosquatting.

Threat: Compromised Upstream Package (in vcpkg Registry)

• Description: A legitimate package within the vcpkg registry (or a dependency of a vcpkg package) is compromised. vcpkg unknowingly distributes the compromised version.
  • Impact:
    • Execution of arbitrary code.
    • Data breaches.
    • Application compromise.
    • Supply chain compromise.
  • Affected vcpkg Component:
    • vcpkg install and vcpkg update commands.
    • The entire vcpkg registry and its package distribution mechanism.
    • Manifest mode (vcpkg.json) dependency resolution.
  • Risk Severity: High
  • Mitigation Strategies:
    • Version Pinning: Pin all dependencies to specific versions.
    • Regular Dependency Auditing: Use vulnerability scanners.
    • Use a Private Registry: More control over package versions and security audits.
    • Binary Caching: Use a secure binary caching solution.
    • Monitor Security Advisories: Stay informed about security advisories.

Threat: Malicious Build Script (in portfile.cmake)

• Description: A compromised or malicious package includes a portfile.cmake (or other build scripts) that contains malicious code. This code is executed during the vcpkg build process.
  • Impact:
    • Execution of arbitrary code on the build server or developer machine.
    • Data exfiltration.
    • Modification of build artifacts.
    • Lateral movement.
  • Affected vcpkg Component:
    • vcpkg install command and its build process.
    • The portfile.cmake execution environment.
    • Any custom build scripts invoked by the portfile.
  • Risk Severity: High
  • Mitigation Strategies:
    • Use a Private Registry: Allows for thorough review of portfile.cmake scripts.
    • Sandboxing: Run the vcpkg build process in a sandboxed environment.
    • Code Review: Carefully review portfile.cmake scripts.
    • Binary Caching: Avoid building packages from source.
    • Least Privilege: Run vcpkg with minimum privileges.

Threat: Vulnerability in vcpkg Itself (e.g., Code Execution)

• Description: vcpkg itself contains a vulnerability that can be exploited by an attacker. This could be triggered by a specially crafted package, a malicious registry, or a manipulated build environment.
  • Impact:
    • Execution of arbitrary code on the machine running vcpkg.
    • Compromise of the build environment.
    • Potential escalation of privileges.
  • Affected vcpkg Component:
    • Potentially any part of the vcpkg codebase:
      • Package parsing logic.
      • Registry interaction code.
      • Build script execution.
      • Command-line argument parsing.
  • Risk Severity: High
  • Mitigation Strategies:
    • Keep vcpkg Updated: Regularly update vcpkg.
    • Monitor Security Advisories: Stay informed.
    • Least Privilege: Run vcpkg with minimum privileges.
    • Input Validation: If contributing to vcpkg, ensure thorough input validation.

Threat: Cache Poisoning

• Description: An attacker gains access to the local vcpkg cache directory and modifies or replaces cached package files with malicious versions.
  • Impact:
    • Execution of arbitrary code during subsequent builds.
    • Compromise of the application.
    • Data exfiltration.
  • Affected vcpkg Component:
    • The vcpkg cache directory.
    • vcpkg install command (when using cached packages).
  • Risk Severity: High
  • Mitigation Strategies:
    • Secure the Cache Directory: Ensure appropriate access controls.
    • Use a Dedicated Build User: Run vcpkg builds under a dedicated user account.
    • Binary Caching: Use a secure, centrally managed binary caching solution.
    • Regularly Clear the Cache: Periodically clear the local vcpkg cache.
    • Integrity Checks (Future): Ideally, vcpkg would provide built-in mechanisms for verifying cache integrity.