attack-tree.md

Attack Tree Analysis for google/flatbuffers

Objective: Compromise Application Using FlatBuffers

Attack Tree Visualization

└── * Compromise Application Using FlatBuffers *
    ├── * Exploit FlatBuffers Parsing Vulnerabilities *
    │   └── * Buffer Overflow/Out-of-Bounds Read *
    │       └── Malformed Buffer Construction
    │           ├── Invalid Offset Values
    │           │   └── Craft buffer with offsets pointing outside buffer boundaries
    │           └── Incorrect Table/Vector Sizes
    │               └── Craft buffer with size fields exceeding actual data
    ├── Schema Mismatch Exploitation
    │   └── Schema Injection/Substitution
    │       └── Supply malicious schema during schema loading process (if application allows external schema loading)
    └── * Logic Bugs in Application Code Handling FlatBuffers Data *
        └── * Data Validation Failures *
            ├── * Range/Boundary Violations *
            │   └── Application assumes data within certain ranges, but FlatBuffers data violates these ranges
            └── * Missing Input Sanitization *
                └── Application uses FlatBuffers data directly in sensitive operations without sanitization

Attack Tree Path: Compromise Application Using FlatBuffers (Critical Node - Root Goal):

• This is the ultimate attacker objective. Success means gaining unauthorized access, control, or causing significant damage to the application.
• It is the starting point for all attack paths.

Attack Tree Path: Exploit FlatBuffers Parsing Vulnerabilities (Critical Node & High-Risk Path Start):

• This path focuses on directly attacking the FlatBuffers parsing process itself.
• Success here can lead to severe consequences like code execution or denial of service.
• It is a critical node because successful exploitation bypasses application logic and directly targets the underlying data handling mechanism.

Attack Tree Path: Buffer Overflow/Out-of-Bounds Read (Critical Node & High-Risk Path):

• Attack Vector: Malformed Buffer Construction (Invalid Offset Values, Incorrect Table/Vector Sizes)
  • Likelihood: Medium
  • Impact: High (Code Execution, Denial of Service)
  • Effort: Medium
  • Skill Level: Medium
  • Detection Difficulty: Medium
• Description: Attackers craft malformed FlatBuffers buffers with incorrect offsets or sizes. When the application parses these buffers, it can lead to reading or writing memory outside the intended buffer boundaries.
• Impact: This can result in:
  • Code Execution: Overwriting critical memory regions to inject and execute malicious code.
  • Denial of Service: Causing crashes or unpredictable behavior due to memory corruption.
  • Information Disclosure: Reading sensitive data from unintended memory locations.
• Mitigation:
  • Use memory-safe languages or employ memory safety techniques.
  • Implement robust fuzzing to detect buffer overflow vulnerabilities.
  • Utilize static and dynamic analysis tools to identify potential memory safety issues.
  • Keep FlatBuffers library updated to benefit from security patches.

Attack Tree Path: Schema Injection/Substitution (High-Risk Path):

• Attack Vector: Supply malicious schema during schema loading process (if application allows external schema loading)
  • Likelihood: Medium (If application design allows external schema loading)
  • Impact: High (Data manipulation, Logic bypass, potentially Code Execution)
  • Effort: Medium
  • Skill Level: Medium
  • Detection Difficulty: Medium
• Description: If the application allows loading FlatBuffers schemas from external sources (e.g., via API, configuration), an attacker might be able to supply a malicious schema.
• Impact: Using a malicious schema can lead to:
  • Data Misinterpretation: The application misinterprets the FlatBuffers data according to the attacker's schema, leading to logic errors and unexpected behavior.
  • Logic Bypass: Attackers can manipulate data structures and types to bypass business logic or access controls.
  • Potential Code Execution: In some scenarios, schema manipulation combined with application logic flaws could potentially lead to code execution.
• Mitigation:
  • Strictly control schema loading processes.
  • Validate schemas before loading them to ensure they are expected and trusted.
  • Use secure channels for schema delivery if loaded externally.
  • Implement schema integrity checks to detect unauthorized modifications.

Attack Tree Path: Logic Bugs in Application Code Handling FlatBuffers Data (Critical Node & High-Risk Path Start):

• This path focuses on vulnerabilities arising from how the application uses the correctly parsed FlatBuffers data.
• Even if FlatBuffers parsing is secure, flaws in application logic can be exploited.
• It is a critical node because it highlights the importance of secure application development practices after FlatBuffers parsing.

Attack Tree Path: Data Validation Failures (Critical Node & High-Risk Path):

• This is a major category of logic bugs and a critical node because it encompasses common and impactful vulnerabilities.
• Failure to validate data deserialized from FlatBuffers is a primary source of application-level vulnerabilities.

Attack Tree Path: Range/Boundary Violations (Critical Node & High-Risk Path):

• Attack Vector: Application assumes data within certain ranges, but FlatBuffers data violates these ranges.
  • Likelihood: High
  • Impact: Medium (Logic errors, data corruption, unexpected behavior, potentially security bypass)
  • Effort: Low
  • Skill Level: Low
  • Detection Difficulty: Medium
• Description: The application makes assumptions about the valid ranges or boundaries of data fields deserialized from FlatBuffers. Attackers can craft FlatBuffers messages that violate these assumptions.
• Impact: This can lead to:
  • Logic Errors: Incorrect application behavior due to out-of-range values.
  • Data Corruption: Writing invalid data to databases or internal application state.
  • Unexpected Behavior: Application crashes or malfunctions due to unhandled boundary conditions.
  • Security Bypass: In some cases, out-of-range values can be used to bypass access controls or business logic checks.
• Mitigation:
  • Implement thorough range and boundary checks for all relevant data fields deserialized from FlatBuffers.
  • Define clear data validation rules based on application requirements.
  • Use assertions or exception handling to gracefully handle out-of-range values.

Attack Tree Path: Missing Input Sanitization (Critical Node & High-Risk Path):

• Attack Vector: Application uses FlatBuffers data directly in sensitive operations without sanitization.
  • Likelihood: Medium
  • Impact: High (Injection vulnerabilities - SQLi, Command Injection, etc.)
  • Effort: Low
  • Skill Level: Low-Medium
  • Detection Difficulty: Medium
• Description: The application directly uses data from FlatBuffers in sensitive operations (e.g., database queries, system commands, URL construction) without proper sanitization or encoding.
• Impact: This can lead to classic injection vulnerabilities:
  • SQL Injection: If FlatBuffers data is used in SQL queries without sanitization.
  • Command Injection: If FlatBuffers data is used in system commands without sanitization.
  • Cross-Site Scripting (XSS): If FlatBuffers data is used in web page output without proper encoding.
  • Other Injection Attacks: Depending on the context, other types of injection attacks might be possible.
• Mitigation:
  • Always sanitize and encode data before using it in sensitive operations.
  • Use parameterized queries or prepared statements to prevent SQL injection.
  • Use safe APIs and libraries for system commands and URL construction.
  • Implement output encoding to prevent XSS vulnerabilities.
  • Follow the principle of least privilege and avoid running sensitive operations with excessive permissions.