threat-modeling.md

Threat Model Analysis for addaleax/natives

Threat: Overwrite Built-in Function Prototype

• Threat: Overwrite Built-in Function Prototype

  • Description: An attacker, having gained some level of code execution, uses natives to access and modify the prototype of a core JavaScript built-in function (e.g., Array.prototype.push, String.prototype.replace, Object.defineProperty). They replace the original function with a malicious version that performs additional actions, such as stealing data, altering control flow, or injecting further malicious code. This affects all subsequent uses of that function within the application. This is a direct use of natives to manipulate core engine functionality.
  • Impact:
    • Data Exfiltration: Sensitive data processed by the modified function can be leaked.
    • Code Injection: The attacker can inject arbitrary code that executes whenever the modified function is called.
    • Application Logic Corruption: The application's behavior becomes unpredictable and unreliable.
    • Bypass Security Checks: If the modified function is part of a security mechanism, the attacker can bypass it.
  • Affected Component: natives module itself, allowing access to any JavaScript built-in object and its prototype (e.g., Array.prototype, String.prototype, Object.prototype, etc.). Specifically, the attacker would likely use natives to get a reference to the built-in object, then directly modify its properties (e.g., Array.prototype.push = ...).
  • Risk Severity: Critical
  • Mitigation Strategies:
    • Freeze Prototypes (Best Practice): Immediately after application startup (and before any untrusted code can execute), use Object.freeze() on all critical built-in prototypes (e.g., Object.freeze(Array.prototype), Object.freeze(String.prototype)). This prevents modification of these prototypes. This is the most effective mitigation.
    • Isolate Untrusted Code: If you must run untrusted code, use a robust sandboxing solution. Node.js's built-in vm module is not sufficient.
    • Code Review: Thoroughly review any code that interacts with natives.
    • Principle of Least Privilege: Run with minimal privileges.

Threat: Access and Leak Internal V8 Data

• Threat: Access and Leak Internal V8 Data

  • Description: An attacker uses natives directly to access internal V8 data structures that are not normally exposed. This could include object layouts, garbage collection metadata, internal caches, or memory regions. This is a direct exploitation of natives's intended purpose.
  • Impact:
    • Information Disclosure: Leakage of sensitive data.
    • Fingerprinting: The attacker can gain information about the V8 version.
    • Potential for Further Exploitation: Leaked information could reveal vulnerabilities.
  • Affected Component: natives module, providing access to internal V8 objects and data structures. The specific components accessed would depend on the attacker's knowledge of V8 internals.
  • Risk Severity: High
  • Mitigation Strategies:
    • Avoid Unnecessary Access: Only use natives for the absolute minimum necessary internal data.
    • Data Sanitization: Rigorously sanitize any data obtained through natives before exposing it.
    • Process Isolation: Run different parts of the application in separate processes.
    • Regular Updates: Keep Node.js (and thus V8) up to date.

Threat: Trigger Denial-of-Service via Garbage Collection Manipulation

• Threat: Trigger Denial-of-Service via Garbage Collection Manipulation

  • Description: An attacker uses natives directly to interfere with V8's garbage collection. This could involve forcing frequent GC cycles, creating uncollectible objects, or disabling GC mechanisms. This leverages natives to access and manipulate core engine components.
  • Impact:
    • Application Unavailability: The application becomes unresponsive or crashes.
    • Performance Degradation: Significant performance reduction.
  • Affected Component: natives module, providing access to V8's garbage collection APIs and internal data structures. The attacker might use functions like %CollectGarbage() (if exposed) or manipulate object properties.
  • Risk Severity: High
  • Mitigation Strategies:
    • Resource Limits: Use OS or containerization features to limit CPU and memory.
    • Avoid natives for GC Control: Do not use natives to directly control garbage collection.
    • Monitoring: Monitor memory usage and garbage collection behavior.

Threat: Modify Internal Timers or Event Loop

• Threat: Modify Internal Timers or Event Loop

  • Description: An attacker uses natives directly to access and modify internal V8 timers or the event loop, disrupting normal operation. This is a direct attack on core engine functionality through natives.
  • Impact:
    • Application Unavailability: The application becomes unresponsive or hangs.
    • Disruption of Functionality: Time-dependent features stop working.
    • Denial of Service: The application is unable to process requests.
  • Affected Component: natives module, providing access to V8's internal timer management and event loop mechanisms.
  • Risk Severity: High
  • Mitigation Strategies:
    • Avoid natives for Timer/Event Loop Manipulation: Do not use natives for this purpose.
    • Timeouts: Implement timeouts for operations that rely on timers or the event loop.
    • Monitoring: Monitor event loop performance.

Threat: Bypass Security Mechanisms via Internal Modification

• Threat: Bypass Security Mechanisms via Internal Modification

  • Description: An attacker uses natives directly to modify internal V8 security mechanisms, such as code signing checks, sandbox escapes, or other internal security features. This is a highly sophisticated, direct attack leveraging natives's access to low-level internals.
  • Impact:
    • Complete System Compromise: The attacker can bypass fundamental security protections.
    • Undetectable Malware: The attacker can install persistent, hard-to-detect malware.
  • Affected Component: natives module, providing access to low-level V8 internals, including security-related code and data structures.
  • Risk Severity: Critical
  • Mitigation Strategies:
    • Avoid natives if at all possible: This is the primary mitigation.
    • Strong Sandboxing: If natives must be used, use a highly restricted sandbox.
    • Regular Security Audits: Conduct regular audits and penetration testing by V8 experts.
    • Keep Node.js Updated: Regularly update Node.js.
    • Principle of Least Privilege: Run with minimal privileges.