Skip to content

Latest commit

 

History

History
77 lines (65 loc) · 4.74 KB

attack-tree.md

File metadata and controls

77 lines (65 loc) · 4.74 KB

Attack Tree Analysis for dart-lang/json_serializable

Objective: Execute Arbitrary Code or Cause DoS via json_serializable

Attack Tree Visualization

Goal: Execute Arbitrary Code or Cause DoS via json_serializable ├── 1. Denial of Service (DoS) │ ├── 1.1 Excessive Resource Consumption │ │ ├── 1.1.1 Deeply Nested JSON !!! │ │ │ └── Exploit: ... │ │ ├── 1.1.2 Large JSON Payloads !!! │ │ │ └── Exploit: ... │ ├── 1.2 Type Mismatch Errors Leading to Unhandled Exceptions *** !!! │ │ └── Exploit: ... │ ├── 2. Arbitrary Code Execution (Less Likely, but Higher Impact) │ ├── 2.2 Vulnerabilities in Custom Converters *** !!! │ │ └── Exploit: ...

Attack Tree Path: 1.1.1 Deeply Nested JSON

  • Exploit: The attacker sends a JSON payload with an extremely large number of nested objects or arrays (e.g., thousands of levels deep). This can overwhelm the parser and lead to excessive memory consumption or stack overflow errors, causing a denial of service.
  • Mitigation:
    • Implement a limit on the maximum nesting depth allowed during JSON deserialization.
    • Consider using a custom JsonFactory with a built-in depth check.
  • Likelihood: Medium
  • Impact: High
  • Effort: Low
  • Skill Level: Novice
  • Detection Difficulty: Medium (Resource exhaustion might be noticeable, but the root cause could be harder to pinpoint)

Attack Tree Path: 1.1.2 Large JSON Payloads

  • Exploit: The attacker sends a JSON payload containing extremely large strings, arrays, or overall data size. This can consume excessive memory and processing time, leading to a denial of service.
  • Mitigation:
    • Enforce a maximum size limit for incoming JSON payloads.
    • Implement size checks before attempting to deserialize the JSON.
  • Likelihood: Medium
  • Impact: High
  • Effort: Low
  • Skill Level: Novice
  • Detection Difficulty: Medium (Similar to deeply nested JSON, resource exhaustion is the primary indicator)

Attack Tree Path: 1.2 Type Mismatch Errors Leading to Unhandled Exceptions

  • Exploit: The attacker sends JSON with data types that do not match the expected types in the Dart classes. For example, sending a string where an integer is expected. If the application does not have robust error handling around the fromJson calls, these type mismatches can lead to unhandled exceptions (TypeError, FormatException), crashing the application and causing a denial of service.
  • Mitigation:
    • Implement comprehensive error handling around all fromJson calls.
    • Use try-catch blocks to specifically catch TypeError and FormatException.
    • Log the errors appropriately.
    • Return a well-defined error response to the client (e.g., an HTTP 400 Bad Request) instead of allowing the application to crash.
  • Likelihood: High (Without proper error handling)
  • Impact: Medium (Application crash, but potentially recoverable)
  • Effort: Very Low
  • Skill Level: Novice
  • Detection Difficulty: Easy (Exceptions are usually logged)

Attack Tree Path: 2.2 Vulnerabilities in Custom Converters

  • Exploit: If the application uses custom JsonConverter implementations, and these converters have vulnerabilities, an attacker can craft malicious JSON input to exploit them. Examples of vulnerabilities include:
    • Executing code based on untrusted JSON input.
    • Performing unsafe type casts.
    • Calling dangerous functions based on input.
    • Logic errors that can be triggered by specific input.
  • Mitigation:
    • Thoroughly review and audit all custom JsonConverter implementations.
    • Never execute code directly based on the content of the JSON input within the converter.
    • Use safe type conversions and avoid any unsafe operations.
    • Perform rigorous input validation within the converter.
    • Consider fuzz testing the converter with a wide range of valid and invalid inputs to identify potential vulnerabilities.
  • Likelihood: Low (Requires a vulnerable custom converter to be present)
  • Impact: Very High (Potential for arbitrary code execution)
  • Effort: Medium to High (Depends on the complexity of the converter and the vulnerability)
  • Skill Level: Advanced to Expert
  • Detection Difficulty: Hard (Requires understanding the converter's code and identifying subtle vulnerabilities)