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Attack Surface Analysis for blankj/androidutilcode

Attack Surface: Cryptographic Misuse

  • Description: Incorrect implementation of cryptographic functions, leading to weak encryption or data exposure.
  • androidutilcode Contribution: Provides EncryptUtils with various encryption and hashing functions (AES, DES, RSA, MD5, SHA). Easy-to-use APIs can lead to incorrect usage without understanding underlying cryptographic principles.
  • Example: A developer uses EncryptUtils.encryptAES() with a hardcoded key and a static IV, making the encryption easily breakable.
  • Impact: Compromise of sensitive data (passwords, personal information, API keys), potentially leading to identity theft, financial loss, or reputational damage.
  • Risk Severity: Critical
  • Mitigation Strategies:
    • Developers:
      • Never use MD5 or SHA-1 for security-sensitive operations.
      • For password hashing, use strong, adaptive hashing algorithms like Argon2, bcrypt, or scrypt (use a dedicated library, not EncryptUtils).
      • For symmetric encryption (AES, DES), use the Android Keystore for key management. Never hardcode keys. Use secure modes of operation (GCM, CBC with proper padding) and random IVs.
      • For asymmetric encryption (RSA), use OAEP padding and sufficiently large key sizes (2048+ bits).
      • Thoroughly understand cryptographic best practices before using any encryption function. Consider using a higher-level library like Tink.

Attack Surface: Command Injection (Shell Execution)

  • Description: Attackers inject malicious commands into shell commands executed by the application.
  • androidutilcode Contribution: Provides ShellUtils.execCmd() for executing shell commands. If user input is directly incorporated into the command string without sanitization, it's vulnerable.
  • Example: An app uses ShellUtils.execCmd("ping " + userInput) to ping a host. An attacker provides input like "; rm -rf /sdcard/*", causing the app to delete files.
  • Impact: Arbitrary code execution, data deletion, device compromise, privilege escalation.
  • Risk Severity: Critical
  • Mitigation Strategies:
    • Developers:
      • Avoid using ShellUtils whenever possible. Explore alternative Android SDK APIs.
      • If ShellUtils must be used, never directly concatenate user input into the command string.
      • Use parameterized commands or rigorously sanitize all user input before passing it to execCmd(). Whitelist allowed characters rather than blacklisting dangerous ones.

Attack Surface: Path Traversal (File I/O)

  • Description: Attackers manipulate file paths to access files outside the intended directory.
  • androidutilcode Contribution: Provides FileUtils and FileIOUtils for file operations. If these utilities don't properly sanitize file paths, they can be exploited.
  • Example: An app uses FileUtils.writeFile(userInput, "data") to write data to a file. An attacker provides a path like "../../../../data/data/com.example.app/databases/" to overwrite the application's database.
  • Impact: Unauthorized access to sensitive files, data leakage, potential system compromise (on rooted devices), data corruption.
  • Risk Severity: High
  • Mitigation Strategies:
    • Developers:
      • Always validate and sanitize user-provided file paths before using them with any androidutilcode file function.
      • Use relative paths within the app's designated storage areas (internal or external with scoped storage). Avoid absolute paths.
      • Enforce the principle of least privilege: the app should only have access to the files it absolutely needs.
      • Use Android's built-in file storage mechanisms and APIs, which provide some built-in protection against path traversal.

Attack Surface: Insecure Data Storage (SharedPreferences)

  • Description: Sensitive data is stored insecurely in SharedPreferences, making it accessible to attackers.
  • androidutilcode Contribution: Provides SPUtils to simplify SharedPreferences access. This can encourage developers to store data in SharedPreferences that should be stored more securely.
  • Example: An app uses SPUtils.put("auth_token", userToken) to store a user's authentication token. On a rooted device, an attacker can retrieve this token and impersonate the user.
  • Impact: Exposure of sensitive data (API keys, tokens, potentially user data), leading to unauthorized access to services or data breaches.
  • Risk Severity: High
  • Mitigation Strategies:
    • Developers:
      • Never store sensitive data (passwords, API keys, tokens) directly in SharedPreferences, even with SPUtils.
      • Use the Android Keystore system for storing sensitive data securely.
      • If using SharedPreferences for non-sensitive data, understand that it's accessible on rooted devices.