attack-tree.md

Attack Tree Analysis for standardnotes/app

Objective: Compromise application using Standard Notes by exploiting vulnerabilities within Standard Notes itself.

Attack Tree Visualization

Compromise Application Using Standard Notes [CRITICAL NODE]
├───[AND] Exploit Client-Side Vulnerabilities in Standard Notes App [CRITICAL NODE] [HIGH RISK PATH]
│   ├───[OR] Cross-Site Scripting (XSS) [HIGH RISK PATH]
│   │   ├───[AND] Stored XSS [HIGH RISK PATH]
│   │   │   └───[ACTION] Inject malicious script into note content, extension settings, or theme configurations that is stored and executed for other users or upon revisiting. [CRITICAL NODE]
│   │   ├───[AND] DOM-based XSS [HIGH RISK PATH]
│   │   │   └───[ACTION] Manipulate DOM elements or client-side routing to inject and execute malicious script. [CRITICAL NODE]
│   │   └───[AND] Dependency Vulnerabilities [HIGH RISK PATH]
│   │       └───[ACTION] Exploit known vulnerabilities in third-party JavaScript libraries used by Standard Notes. [CRITICAL NODE]
├───[AND] Exploit Encryption Weaknesses or Implementation Flaws [CRITICAL NODE] [HIGH RISK PATH]
│   ├───[OR] Weak Cryptographic Algorithms (Less likely, but consider legacy issues)
│   │   └───[ACTION] Identify and exploit usage of outdated or weak cryptographic algorithms if present. [CRITICAL NODE]
│   ├───[OR] Flaws in Encryption Implementation [HIGH RISK PATH]
│   │   ├───[AND] Incorrect Key Derivation or Management [HIGH RISK PATH]
│   │   │   └───[ACTION] Exploit weaknesses in how encryption keys are derived, stored, or managed, potentially leading to key compromise. [CRITICAL NODE]
│   └───[OR] Key Leakage or Exposure [HIGH RISK PATH]
│       ├───[AND] Insecure Key Storage [HIGH RISK PATH]
│       │   └───[ACTION] Recover encryption keys if stored insecurely on the client-side (e.g., local storage, insecure file system permissions). [CRITICAL NODE]
├───[AND] Exploit Extension/Plugin System Vulnerabilities [CRITICAL NODE] [HIGH RISK PATH]
│   ├───[OR] Malicious Extension Installation [HIGH RISK PATH]
│   │   ├───[AND] Social Engineering [HIGH RISK PATH]
│   │   │   └───[ACTION] Trick user into installing a malicious extension designed to steal data or compromise the application. [CRITICAL NODE]
│   ├───[OR] Vulnerabilities in Extension API [HIGH RISK PATH]
│   │   ├───[AND] Insufficient Access Control in API [HIGH RISK PATH]
│   │   │   └───[ACTION] Exploit weaknesses in the extension API to allow extensions to access more data or functionality than intended. [CRITICAL NODE]
└───[AND] Exploit Authentication and Session Management Vulnerabilities (Less directly related to app itself, but consider integration points)
    ├───[OR] Session Hijacking (If web version or API access is used) [HIGH RISK PATH]
    │   ├───[AND] Session Token Theft via XSS (See Client-Side XSS above) [HIGH RISK PATH]
    │   │   └───[ACTION] Steal session tokens via XSS vulnerabilities to impersonate a user. [CRITICAL NODE]

Attack Tree Path: Compromise Application Using Standard Notes [CRITICAL NODE]

• This is the root goal and a critical node because it represents the ultimate objective of the attacker. Success here means full compromise of the application and potentially user data.

Attack Tree Path: Exploit Client-Side Vulnerabilities in Standard Notes App [CRITICAL NODE] [HIGH RISK PATH]

• Client-side vulnerabilities are a high-risk path because they are often easier to exploit than server-side issues and can directly impact user sessions and data within the application. This node is critical as it's a major entry point for attacks.

  • Cross-Site Scripting (XSS) [HIGH RISK PATH]

    • XSS is a high-risk path due to its potential for account takeover, data theft, and malware distribution. It targets the client-side execution environment.

    • Stored XSS [HIGH RISK PATH] [CRITICAL NODE]

      • Attack Vector: Inject malicious JavaScript code into persistent storage locations within Standard Notes, such as note content, extension settings, or theme configurations. When other users view or interact with this stored data, or when the original user revisits it, the malicious script executes in their browsers.
      • Impact: Account takeover, data theft (including encrypted notes if encryption is compromised via XSS), malware distribution, persistent compromise of user accounts.
      • Mitigation: Robust input sanitization and output encoding, Content Security Policy (CSP), regular security audits and penetration testing.

    • DOM-based XSS [HIGH RISK PATH] [CRITICAL NODE]

      • Attack Vector: Manipulate the Document Object Model (DOM) or client-side routing mechanisms of the Standard Notes application to inject and execute malicious JavaScript code directly within the user's browser. This often involves exploiting vulnerabilities in client-side JavaScript code that processes user input or application state.
      • Impact: Similar to Stored XSS: Account takeover, data theft, malware distribution.
      • Mitigation: Secure coding practices in client-side JavaScript, careful handling of DOM manipulation, security audits focusing on client-side code.

    • Dependency Vulnerabilities [HIGH RISK PATH] [CRITICAL NODE]

      • Attack Vector: Exploit known security vulnerabilities in third-party JavaScript libraries used by the Standard Notes application. Attackers can leverage publicly available exploits or develop custom exploits targeting these vulnerabilities.
      • Impact: Remote Code Execution (RCE), Cross-Site Scripting (XSS), Denial of Service (DoS), data theft, depending on the specific vulnerability in the dependency.
      • Mitigation: Regular dependency updates, vulnerability scanning tools, using Software Composition Analysis (SCA) to monitor dependencies, and having a plan for rapid patching.

Attack Tree Path: Cross-Site Scripting (XSS) [HIGH RISK PATH]

    *   XSS is a high-risk path due to its potential for account takeover, data theft, and malware distribution. It targets the client-side execution environment.

Attack Tree Path: Stored XSS [HIGH RISK PATH] [CRITICAL NODE]

        *   **Attack Vector:** Inject malicious JavaScript code into persistent storage locations within Standard Notes, such as note content, extension settings, or theme configurations. When other users view or interact with this stored data, or when the original user revisits it, the malicious script executes in their browsers.
        *   **Impact:** Account takeover, data theft (including encrypted notes if encryption is compromised via XSS), malware distribution, persistent compromise of user accounts.
        *   **Mitigation:** Robust input sanitization and output encoding, Content Security Policy (CSP), regular security audits and penetration testing.

Attack Tree Path: DOM-based XSS [HIGH RISK PATH] [CRITICAL NODE]

        *   **Attack Vector:** Manipulate the Document Object Model (DOM) or client-side routing mechanisms of the Standard Notes application to inject and execute malicious JavaScript code directly within the user's browser. This often involves exploiting vulnerabilities in client-side JavaScript code that processes user input or application state.
        *   **Impact:** Similar to Stored XSS: Account takeover, data theft, malware distribution.
        *   **Mitigation:** Secure coding practices in client-side JavaScript, careful handling of DOM manipulation, security audits focusing on client-side code.

Attack Tree Path: Dependency Vulnerabilities [HIGH RISK PATH] [CRITICAL NODE]

        *   **Attack Vector:** Exploit known security vulnerabilities in third-party JavaScript libraries used by the Standard Notes application. Attackers can leverage publicly available exploits or develop custom exploits targeting these vulnerabilities.
        *   **Impact:** Remote Code Execution (RCE), Cross-Site Scripting (XSS), Denial of Service (DoS), data theft, depending on the specific vulnerability in the dependency.
        *   **Mitigation:** Regular dependency updates, vulnerability scanning tools, using Software Composition Analysis (SCA) to monitor dependencies, and having a plan for rapid patching.

Attack Tree Path: Exploit Encryption Weaknesses or Implementation Flaws [CRITICAL NODE] [HIGH RISK PATH]

• This is a critical node and high-risk path because Standard Notes relies heavily on encryption for security and privacy. Any weakness here directly undermines the core security promise of the application.

  • Weak Cryptographic Algorithms (Less likely, but consider legacy issues) [CRITICAL NODE]

    • Attack Vector: Identify and exploit the use of outdated or weak cryptographic algorithms within Standard Notes. This could be due to legacy code, misconfigurations, or vulnerabilities in the chosen algorithms themselves.
    • Impact: Complete data compromise. If weak algorithms are used for encryption, attackers can decrypt all encrypted notes and data.
    • Mitigation: Use strong, modern, and well-vetted cryptographic algorithms. Regularly review and update cryptographic libraries and implementations. Cryptographic audits.

  • Flaws in Encryption Implementation [HIGH RISK PATH]

    • Incorrect Key Derivation or Management [HIGH RISK PATH] [CRITICAL NODE]
      • Attack Vector: Exploit weaknesses in how Standard Notes derives, stores, or manages encryption keys. This could include weak key derivation functions, insecure key storage locations (especially client-side), or vulnerabilities in key exchange protocols.
      • Impact: Key compromise. If encryption keys are compromised, attackers can decrypt all encrypted data.
      • Mitigation: Implement robust and secure key derivation functions, secure key storage mechanisms (consider hardware-backed storage where possible), secure key exchange protocols, and regular cryptographic audits focusing on key management.

  • Key Leakage or Exposure [HIGH RISK PATH]

    • Insecure Key Storage [HIGH RISK PATH] [CRITICAL NODE]
      • Attack Vector: Recover encryption keys if they are stored insecurely on the client-side. This could involve accessing local storage, insecure file system permissions, or other vulnerable storage mechanisms where keys are inadvertently exposed.
      • Impact: Key compromise, leading to decryption of all encrypted data.
      • Mitigation: Avoid storing encryption keys insecurely on the client-side. Use secure storage mechanisms provided by the operating system or hardware. Implement proper file system permissions and access controls.

Attack Tree Path: Weak Cryptographic Algorithms (Less likely, but consider legacy issues) [CRITICAL NODE]

    *   **Attack Vector:** Identify and exploit the use of outdated or weak cryptographic algorithms within Standard Notes. This could be due to legacy code, misconfigurations, or vulnerabilities in the chosen algorithms themselves.
    *   **Impact:** Complete data compromise. If weak algorithms are used for encryption, attackers can decrypt all encrypted notes and data.
    *   **Mitigation:** Use strong, modern, and well-vetted cryptographic algorithms. Regularly review and update cryptographic libraries and implementations. Cryptographic audits.

Attack Tree Path: Flaws in Encryption Implementation [HIGH RISK PATH]

    *   **Incorrect Key Derivation or Management [HIGH RISK PATH] [CRITICAL NODE]**
        *   **Attack Vector:** Exploit weaknesses in how Standard Notes derives, stores, or manages encryption keys. This could include weak key derivation functions, insecure key storage locations (especially client-side), or vulnerabilities in key exchange protocols.
        *   **Impact:** Key compromise. If encryption keys are compromised, attackers can decrypt all encrypted data.
        *   **Mitigation:** Implement robust and secure key derivation functions, secure key storage mechanisms (consider hardware-backed storage where possible), secure key exchange protocols, and regular cryptographic audits focusing on key management.

Attack Tree Path: Incorrect Key Derivation or Management [HIGH RISK PATH] [CRITICAL NODE]

        *   **Attack Vector:** Exploit weaknesses in how Standard Notes derives, stores, or manages encryption keys. This could include weak key derivation functions, insecure key storage locations (especially client-side), or vulnerabilities in key exchange protocols.
        *   **Impact:** Key compromise. If encryption keys are compromised, attackers can decrypt all encrypted data.
        *   **Mitigation:** Implement robust and secure key derivation functions, secure key storage mechanisms (consider hardware-backed storage where possible), secure key exchange protocols, and regular cryptographic audits focusing on key management.

Attack Tree Path: Key Leakage or Exposure [HIGH RISK PATH]

    *   **Insecure Key Storage [HIGH RISK PATH] [CRITICAL NODE]**
        *   **Attack Vector:** Recover encryption keys if they are stored insecurely on the client-side. This could involve accessing local storage, insecure file system permissions, or other vulnerable storage mechanisms where keys are inadvertently exposed.
        *   **Impact:** Key compromise, leading to decryption of all encrypted data.
        *   **Mitigation:** Avoid storing encryption keys insecurely on the client-side. Use secure storage mechanisms provided by the operating system or hardware. Implement proper file system permissions and access controls.

Attack Tree Path: Insecure Key Storage [HIGH RISK PATH] [CRITICAL NODE]

        *   **Attack Vector:** Recover encryption keys if they are stored insecurely on the client-side. This could involve accessing local storage, insecure file system permissions, or other vulnerable storage mechanisms where keys are inadvertently exposed.
        *   **Impact:** Key compromise, leading to decryption of all encrypted data.
        *   **Mitigation:** Avoid storing encryption keys insecurely on the client-side. Use secure storage mechanisms provided by the operating system or hardware. Implement proper file system permissions and access controls.

Attack Tree Path: Exploit Extension/Plugin System Vulnerabilities [CRITICAL NODE] [HIGH RISK PATH]

• The extension system is a critical node and high-risk path because extensions can significantly extend the functionality of Standard Notes and potentially introduce new vulnerabilities if not properly secured.

  • Malicious Extension Installation [HIGH RISK PATH]

    • Social Engineering [HIGH RISK PATH] [CRITICAL NODE]
      • Attack Vector: Trick users into installing malicious extensions designed to steal data, inject malware, or compromise the application. This relies on social engineering tactics to convince users to install untrusted extensions.
      • Impact: High impact as malicious extensions can have broad access to application data and functionality, leading to data theft, account compromise, and potentially system compromise.
      • Mitigation: User education and awareness training about the risks of installing untrusted extensions. Implement a clear and secure extension installation process. Consider code signing and sandboxing for extensions.

  • Vulnerabilities in Extension API [HIGH RISK PATH]

    • Insufficient Access Control in API [HIGH RISK PATH] [CRITICAL NODE]
      • Attack Vector: Exploit weaknesses in the extension API to allow extensions to access more data or functionality than they are intended to have. This could be due to flaws in API design or implementation of access control mechanisms.
      • Impact: Extensions gaining unauthorized access can lead to data theft, privilege escalation within the application, and unexpected or malicious behavior.
      • Mitigation: Design a secure and well-defined extension API with least privilege principles. Implement robust access control mechanisms within the API. Conduct security audits of the API and extension handling code.

Attack Tree Path: Malicious Extension Installation [HIGH RISK PATH]

    *   **Social Engineering [HIGH RISK PATH] [CRITICAL NODE]**
        *   **Attack Vector:** Trick users into installing malicious extensions designed to steal data, inject malware, or compromise the application. This relies on social engineering tactics to convince users to install untrusted extensions.
        *   **Impact:** High impact as malicious extensions can have broad access to application data and functionality, leading to data theft, account compromise, and potentially system compromise.
        *   **Mitigation:** User education and awareness training about the risks of installing untrusted extensions. Implement a clear and secure extension installation process. Consider code signing and sandboxing for extensions.

Attack Tree Path: Social Engineering [HIGH RISK PATH] [CRITICAL NODE]

        *   **Attack Vector:** Trick users into installing malicious extensions designed to steal data, inject malware, or compromise the application. This relies on social engineering tactics to convince users to install untrusted extensions.
        *   **Impact:** High impact as malicious extensions can have broad access to application data and functionality, leading to data theft, account compromise, and potentially system compromise.
        *   **Mitigation:** User education and awareness training about the risks of installing untrusted extensions. Implement a clear and secure extension installation process. Consider code signing and sandboxing for extensions.

Attack Tree Path: Vulnerabilities in Extension API [HIGH RISK PATH]

    *   **Insufficient Access Control in API [HIGH RISK PATH] [CRITICAL NODE]**
        *   **Attack Vector:** Exploit weaknesses in the extension API to allow extensions to access more data or functionality than they are intended to have. This could be due to flaws in API design or implementation of access control mechanisms.
        *   **Impact:** Extensions gaining unauthorized access can lead to data theft, privilege escalation within the application, and unexpected or malicious behavior.
        *   **Mitigation:** Design a secure and well-defined extension API with least privilege principles. Implement robust access control mechanisms within the API. Conduct security audits of the API and extension handling code.

Attack Tree Path: Insufficient Access Control in API [HIGH RISK PATH] [CRITICAL NODE]

        *   **Attack Vector:** Exploit weaknesses in the extension API to allow extensions to access more data or functionality than they are intended to have. This could be due to flaws in API design or implementation of access control mechanisms.
        *   **Impact:** Extensions gaining unauthorized access can lead to data theft, privilege escalation within the application, and unexpected or malicious behavior.
        *   **Mitigation:** Design a secure and well-defined extension API with least privilege principles. Implement robust access control mechanisms within the API. Conduct security audits of the API and extension handling code.

Attack Tree Path: Exploit Authentication and Session Management Vulnerabilities (Less directly related to app itself, but consider integration points) [HIGH RISK PATH]

• Session Hijacking (If web version or API access is used) [HIGH RISK PATH] * Session Token Theft via XSS (See Client-Side XSS above) [HIGH RISK PATH] [CRITICAL NODE] * Attack Vector: Leverage Cross-Site Scripting (XSS) vulnerabilities (specifically Stored or DOM-based XSS) to steal user session tokens. Once an attacker has a valid session token, they can impersonate the user and gain unauthorized access to their account. * Impact: Account takeover. Full access to the user's account and data, including encrypted notes. * Mitigation: Primarily mitigate XSS vulnerabilities (as detailed above). Use secure session management practices, including HTTP-only and Secure flags for cookies, and consider using short session timeouts.

Attack Tree Path: Session Hijacking (If web version or API access is used) [HIGH RISK PATH]

    *   **Session Token Theft via XSS (See Client-Side XSS above) [HIGH RISK PATH] [CRITICAL NODE]**
        *   **Attack Vector:** Leverage Cross-Site Scripting (XSS) vulnerabilities (specifically Stored or DOM-based XSS) to steal user session tokens. Once an attacker has a valid session token, they can impersonate the user and gain unauthorized access to their account.
        *   **Impact:** Account takeover. Full access to the user's account and data, including encrypted notes.
        *   **Mitigation:** Primarily mitigate XSS vulnerabilities (as detailed above). Use secure session management practices, including HTTP-only and Secure flags for cookies, and consider using short session timeouts.

Attack Tree Path: Session Token Theft via XSS (See Client-Side XSS above) [HIGH RISK PATH] [CRITICAL NODE]

        *   **Attack Vector:** Leverage Cross-Site Scripting (XSS) vulnerabilities (specifically Stored or DOM-based XSS) to steal user session tokens. Once an attacker has a valid session token, they can impersonate the user and gain unauthorized access to their account.
        *   **Impact:** Account takeover. Full access to the user's account and data, including encrypted notes.
        *   **Mitigation:** Primarily mitigate XSS vulnerabilities (as detailed above). Use secure session management practices, including HTTP-only and Secure flags for cookies, and consider using short session timeouts.