Skip to content

Latest commit

 

History

History
101 lines (71 loc) · 9.82 KB

attack-tree.md

File metadata and controls

101 lines (71 loc) · 9.82 KB

Attack Tree Analysis for google/tink

Objective: Compromise application using Tink by exploiting weaknesses or vulnerabilities within Tink or its usage.

Attack Tree Visualization

Root: Compromise Application Using Tink (High-Risk Focus)

    ├─── 1. Exploit Tink Library Vulnerabilities
    │    └─── 1.1. Cryptographic Algorithm Weakness
    │         └─── 1.1.2. Implementation Flaws in Algorithm **[CRITICAL NODE]**

    └─── 2. Exploit Application's Tink Integration Weaknesses **[HIGH-RISK PATH]**
         ├─── 2.1. Insecure Key Storage **[HIGH-RISK PATH]**
         │    ├─── 2.1.1. Keys Stored in Plaintext **[CRITICAL NODE]** **[HIGH-RISK PATH]**
         │    └─── 2.1.3. Key Leakage via Logs/Debugging **[HIGH-RISK PATH]**
         └─── 2.3. Misuse of Tink Primitives in Application Logic **[HIGH-RISK PATH]**
              └─── 2.3.1. Incorrect AEAD Usage (Nonce Reuse) **[CRITICAL NODE]** **[HIGH-RISK PATH]**
              └─── 2.3.4. Ignoring Tink Security Recommendations/Warnings **[HIGH-RISK PATH]**
         └─── 1.3. API Misuse Vulnerabilities in Tink Library
              └─── 1.3.1. Incorrect Parameter Usage **[CRITICAL NODE]**

Attack Tree Path: 1.1.2. Implementation Flaws in Algorithm [CRITICAL NODE]

  • Attack Vector:
    • Code Analysis and Reverse Engineering: Attacker meticulously analyzes Tink's source code, specifically the implementations of cryptographic algorithms (e.g., AES-GCM, ECDSA). They look for subtle bugs, off-by-one errors, incorrect state management, or other implementation flaws that could lead to exploitable vulnerabilities.
    • Fuzzing and Differential Fault Analysis: Attacker uses fuzzing techniques to feed malformed or unexpected inputs to Tink's cryptographic functions, hoping to trigger crashes or unexpected behavior that reveals implementation flaws. Differential fault analysis might involve inducing faults (e.g., through power glitches in hardware scenarios, or software-based fault injection) to observe how the algorithm deviates and potentially leak information.
  • Exploitation: If a flaw is found, the attacker could potentially:
    • Bypass Encryption: Decrypt ciphertext without the key.
    • Forge Signatures: Create valid signatures for malicious data.
    • Cause Denial of Service: Trigger crashes or infinite loops in cryptographic operations.

Attack Tree Path: 2. Exploit Application's Tink Integration Weaknesses [HIGH-RISK PATH]

Attack Tree Path: 2.1. Insecure Key Storage [HIGH-RISK PATH]

Attack Tree Path: 2.1.1. Keys Stored in Plaintext [CRITICAL NODE] [HIGH-RISK PATH]

  • Attack Vector:
    • File System Access: Attacker gains unauthorized access to the application's file system through various means (e.g., web server vulnerabilities, compromised accounts, insider threat). They then search for files containing keys, often looking in configuration files, source code repositories within the deployment, or application data directories.
    • Code Inspection: Attacker examines the application's source code (if accessible through vulnerabilities like source code disclosure or decompilation) to find hardcoded keys directly embedded in the code.
    • Configuration Review: Attacker analyzes application configuration files (e.g., .ini, .yaml, .json, environment variables if exposed) to find keys stored as plaintext configuration parameters.
  • Exploitation: Once plaintext keys are obtained, the attacker has complete control over the cryptographic system:
    • Data Decryption: Decrypt all data encrypted with the compromised keys.
    • Data Forgery: Forge signatures, create valid authentication tokens, manipulate encrypted data.
    • Impersonation: Impersonate legitimate users or services if keys are used for authentication.

Attack Tree Path: 2.1.3. Key Leakage via Logs/Debugging [HIGH-RISK PATH]

  • Attack Vector:
    • Log File Access: Attacker gains access to application log files (e.g., web server logs, application logs, system logs) through vulnerabilities or unauthorized access. They then search log files for accidentally logged keys.
    • Error Reporting Analysis: Attacker analyzes error reports or debugging outputs generated by the application, looking for cases where keys might have been included in error messages or stack traces during development or debugging phases that were inadvertently left enabled in production.
    • Debugging Interfaces: If debugging interfaces are unintentionally exposed in production (e.g., debug endpoints, remote debugging ports), attacker might use these to extract keys from the application's memory or runtime environment.
  • Exploitation: If keys are leaked through logs or debugging information, the attacker can:
    • Data Decryption: Decrypt data encrypted with the leaked keys.
    • Data Forgery: Forge signatures, manipulate encrypted data.
    • Gain System Access: Potentially use leaked keys for authentication if they are used for system-level access.

Attack Tree Path: 2.3. Misuse of Tink Primitives in Application Logic [HIGH-RISK PATH]

Attack Tree Path: 2.3.1. Incorrect AEAD Usage (Nonce Reuse) [CRITICAL NODE] [HIGH-RISK PATH]

  • Attack Vector:
    • Code Analysis: Attacker analyzes the application's code to understand how nonces are generated and used with AEAD encryption (e.g., Aead.encryptDeterministically, Aead.encrypt). They look for flaws in nonce generation logic, such as using predictable nonces, static nonces, or reusing nonces across multiple encryption operations with the same key.
    • Traffic Analysis: Attacker intercepts network traffic or analyzes stored encrypted data to observe nonce patterns. If nonces are repeated or predictable, it indicates potential nonce reuse.
  • Exploitation: Nonce reuse in AEAD algorithms is a critical cryptographic error. It can lead to:
    • Plaintext Recovery: If the same nonce is used to encrypt two different plaintexts with the same key, the attacker can often recover significant portions of both plaintexts by XORing the ciphertexts.
    • Forgery Attacks: In some AEAD modes, nonce reuse can also enable attackers to forge ciphertexts.

Attack Tree Path: 2.3.4. Ignoring Tink Security Recommendations/Warnings [HIGH-RISK PATH]

  • Attack Vector:
    • Code Review (Internal or External): Attacker (or internal auditor) reviews the application's code and development practices, specifically looking for instances where developers have ignored security warnings or recommendations from Tink's documentation, API warnings, or security best practices. This could include using deprecated APIs without understanding the risks, disabling security features, or misconfiguring Tink based on outdated or incorrect information.
    • Security Audits and Penetration Testing: Security audits and penetration tests can uncover instances where developers have deviated from secure coding practices recommended by Tink, leading to exploitable vulnerabilities.
  • Exploitation: Ignoring security recommendations can lead to a wide range of vulnerabilities depending on the specific recommendation ignored. Examples include:
    • Using Weak Algorithms: If recommendations to use stronger algorithms are ignored, the application might be vulnerable to attacks against weaker algorithms.
    • Insecure Key Management: Ignoring key management best practices can lead to key compromise.
    • Misconfigured Primitives: Ignoring warnings about proper primitive usage can lead to vulnerabilities like nonce reuse or incorrect signature verification.

Attack Tree Path: 1.3. API Misuse Vulnerabilities in Tink Library

Attack Tree Path: 1.3.1. Incorrect Parameter Usage [CRITICAL NODE]

  • Attack Vector:
    • Code Analysis: Attacker analyzes the application's code to understand how Tink APIs are used, focusing on the parameters passed to Tink functions. They look for cases where developers might be using incorrect parameter types, sizes, or values that lead to insecure configurations. Examples include using weak key sizes, incorrect encryption modes, or providing invalid input formats.
    • API Fuzzing (Application Level): Attacker fuzzes the application's API endpoints that interact with Tink, sending unexpected or malformed parameters to Tink functions through the application's interface. This can reveal vulnerabilities caused by incorrect parameter handling.
  • Exploitation: Incorrect parameter usage can result in:
    • Weakened Cryptography: Using weak key sizes or algorithms reduces the security strength of the encryption or signature schemes.
    • Algorithm Mismatches: Incorrect parameter types or algorithm specifications can lead to mismatches and potential vulnerabilities.
    • Unexpected Behavior: Incorrect parameters can cause unexpected behavior in Tink, potentially leading to crashes or exploitable conditions.