attack-tree.md

Attack Tree Analysis for matrix-org/synapse

Objective: Compromise Application Using Synapse by Exploiting Synapse Weaknesses (Focused on High-Risk Paths)

Attack Tree Visualization

Root Goal: Compromise Application Using Synapse [CR]
├── 1. Exploit Synapse Client-Server API Vulnerabilities [HR]
│   ├── 1.1. Authentication and Authorization Bypass [HR] [CR]
│   │   ├── 1.1.1. Session Hijacking [HR]
│   │   │   └── 1.1.1.3. Credential Stuffing/Brute-Force Attacks (Synapse rate limiting weaknesses) [HR]
│   │   ├── 1.1.2. Privilege Escalation [HR] [CR]
│   │   │   └── 1.1.2.2. Bypassing access controls due to Synapse misconfiguration [HR]
│   ├── 1.2. Input Validation Vulnerabilities
│   │   └── 1.2.2. Denial of Service (DoS) via Malformed Requests
│   │       └── 1.2.2.1. Sending excessively large or complex requests to overload Synapse resources [HR]
│   ├── 1.3. Logic Flaws in Synapse API
│   │       └── 1.3.1. Business Logic Exploitation
│   │           └── 1.3.1.2. Exploiting rate limiting bypasses to perform actions at scale
│   │               └── ... (DoS via rate limit bypass path)
│   │       └── 1.3.2. Data Leakage via API Responses
│   │           └── 1.3.2.1. Exploiting API endpoints to reveal sensitive information
│   │               └── ... (Information gathering path)
├── 2. Exploit Synapse Federation Vulnerabilities
│   └── 2.1. Malicious Federated Server Compromise
│       └── 2.1.2. Denial of Service via Federated Traffic
│           └── 2.1.2.1. Overwhelm target Synapse with excessive federation traffic from compromised servers [HR]
├── 3. Exploit Synapse Server-Side Vulnerabilities [HR]
│   ├── 3.1. Operating System and Dependency Vulnerabilities [HR]
│   │   ├── 3.1.1. Exploiting known vulnerabilities in underlying OS (Linux, etc.) [HR]
│   │   │   └── 3.1.1.1. Privilege escalation via OS kernel exploits [CR]
│   │   ├── 3.1.2. Exploiting vulnerabilities in Python runtime or libraries used by Synapse [HR]
│   │   │   └── 3.1.2.1. Remote Code Execution (RCE) via vulnerable Python libraries [CR]
│   ├── 3.2. Synapse Configuration and Deployment Weaknesses [HR]
│   │   ├── 3.2.1. Misconfiguration of Synapse settings [HR]
│   │   │   ├── 3.2.1.1. Insecure default configurations left unchanged [HR]
│   │   │   └── 3.2.1.2. Overly permissive access controls or insecure feature enablement [HR]
│   │   ├── 3.2.2. Insecure Deployment Practices [HR]
│   │   │   ├── 3.2.2.1. Running Synapse with overly broad permissions [HR]
│   │   │   ├── 3.2.2.2. Exposing unnecessary Synapse ports or services to the public internet [HR]
│   │   │   └── 3.2.2.3. Lack of proper network segmentation and firewall rules [HR]
│   ├── 3.3. Synapse Code Vulnerabilities (Bugs in Synapse itself) [CR]
│   │   └── 3.3.1. Remote Code Execution (RCE) in Synapse Core [CR]
│   │       └── 3.3.1.1. Exploiting vulnerabilities in Synapse's Python code to execute arbitrary code on the server [CR]
├── 4. Social Engineering and Phishing (Indirectly related to Synapse) [HR]
│   ├── 4.1. Compromise User Credentials [HR]
│   │   ├── 4.1.1. Phishing attacks targeting Synapse users to steal credentials [HR]
│   │   │   └── 4.1.1.1. Spear phishing emails or messages mimicking Synapse login pages [HR]
│   │   ├── 4.1.2. Social engineering to obtain user credentials [HR]
│   │   │   └── 4.1.2.1. Tricking users into revealing passwords or API keys [HR]
│   │   ├── 4.1.3. Credential reuse attacks if users use same passwords elsewhere [HR]
│   │   │   └── 4.1.3.1. Exploiting leaked credentials from other services to access Synapse accounts [HR]
│   ├── 4.2. Compromise Admin Credentials [HR] [CR]
│   │   ├── 4.2.1. Phishing attacks targeting Synapse administrators [HR]
│   │   │   └── 4.2.1.1. Spear phishing emails targeting admins with malicious attachments or links [HR]
│   │   ├── 4.2.2. Social engineering to obtain admin credentials [HR]
│   │   │   └── 4.2.2.1. Impersonating legitimate personnel to trick admins into revealing credentials [HR]
│   │   ├── 4.2.3. Weak or default admin passwords [HR]
│   │   │   └── 4.2.3.1. Exploiting default or easily guessable admin passwords if not changed [HR]

Attack Tree Path: 1. Exploit Synapse Client-Server API Vulnerabilities [HR]

Attack Vector: Attackers target vulnerabilities in the Synapse Client-Server API, which is the primary interface for client applications to interact with the Synapse server.

• Breakdown:
  • 1.1. Authentication and Authorization Bypass [HR] [CR]:
    • 1.1.1. Session Hijacking [HR]:
      • 1.1.1.3. Credential Stuffing/Brute-Force Attacks (Synapse rate limiting weaknesses) [HR]:
        • Attack Vector: Attackers use lists of compromised credentials (usernames and passwords from data breaches) or automated brute-force tools to guess user credentials. Weak Synapse rate limiting or password policies can make this attack more effective.
        • How: Attackers send numerous login requests to the Synapse server, attempting different username/password combinations. If successful, they gain access to user accounts without needing to exploit code vulnerabilities.
    • 1.1.2. Privilege Escalation [HR] [CR]:
      • 1.1.2.2. Bypassing access controls due to Synapse misconfiguration [HR]:
        • Attack Vector: Synapse access controls are misconfigured, allowing users to perform actions they should not be authorized to do. This could be due to overly permissive default settings or administrator errors.
        • How: Attackers identify misconfigured access controls (e.g., in room permissions, admin roles, API endpoint authorization). They then exploit these misconfigurations to gain elevated privileges, potentially becoming administrators or accessing sensitive data they shouldn't.
  • 1.2. Input Validation Vulnerabilities:
    • 1.2.2. Denial of Service (DoS) via Malformed Requests:
      • 1.2.2.1. Sending excessively large or complex requests to overload Synapse resources [HR]:
        • Attack Vector: Attackers send intentionally crafted API requests that are very large, complex, or resource-intensive to process. This can overwhelm the Synapse server, leading to denial of service.
        • How: Attackers craft requests that exploit weaknesses in Synapse's request handling. This might involve sending extremely long requests, deeply nested JSON payloads, or requests that trigger inefficient algorithms in Synapse's processing logic.
  • 1.3. Logic Flaws in Synapse API:
    • 1.3.1. Business Logic Exploitation:
      • 1.3.1.2. Exploiting rate limiting bypasses to perform actions at scale:
        • Attack Vector: Attackers find ways to circumvent Synapse's rate limiting mechanisms. This allows them to perform actions at a much higher rate than intended, potentially leading to abuse, resource exhaustion, or DoS.
        • How: Attackers analyze Synapse's rate limiting implementation and identify bypass techniques. This could involve using multiple accounts, manipulating request headers, or exploiting flaws in the rate limiting logic itself.
    • 1.3.2. Data Leakage via API Responses:
      • 1.3.2.1. Exploiting API endpoints to reveal sensitive information:
        • Attack Vector: Synapse API endpoints, due to design flaws or bugs, might inadvertently expose sensitive information in their responses. This could include user data, room metadata, or server configuration details.
        • How: Attackers probe different API endpoints, looking for responses that contain more information than they should. This might involve manipulating request parameters or exploiting vulnerabilities in API response filtering or sanitization.

Attack Tree Path: 2. Exploit Synapse Federation Vulnerabilities

Attack Vector: Attackers exploit vulnerabilities related to Synapse's federation features, which allow it to communicate with other Matrix servers.

• Breakdown:
  • 2.1. Malicious Federated Server Compromise:
    • 2.1.2. Denial of Service via Federated Traffic:
      • 2.1.2.1. Overwhelm target Synapse with excessive federation traffic from compromised servers [HR]:
        • Attack Vector: Attackers compromise or control a federated Matrix server and use it to flood the target Synapse server with excessive federation traffic.
        • How: Attackers use a compromised federated server to send a large volume of federation requests to the target Synapse server. This can overwhelm the target server's resources, leading to denial of service for its users.

Attack Tree Path: 3. Exploit Synapse Server-Side Vulnerabilities [HR]

Attack Vector: Attackers target vulnerabilities in the Synapse server software itself, its underlying operating system, or its dependencies.

• Breakdown:
  • 3.1. Operating System and Dependency Vulnerabilities [HR]:
    • 3.1.1. Exploiting known vulnerabilities in underlying OS (Linux, etc.) [HR]:
      • 3.1.1.1. Privilege escalation via OS kernel exploits [CR]:
        • Attack Vector: The Synapse server's operating system (e.g., Linux) has known vulnerabilities, particularly in the kernel, that can be exploited to gain elevated privileges.
        • How: Attackers identify and exploit known kernel vulnerabilities on the Synapse server. Publicly available exploits might be used if the server is running an outdated or unpatched kernel. Successful exploitation can lead to root-level access, granting full control over the server.
    • 3.1.2. Exploiting vulnerabilities in Python runtime or libraries used by Synapse [HR]:
      • 3.1.2.1. Remote Code Execution (RCE) via vulnerable Python libraries [CR]:
        • Attack Vector: Python libraries used by Synapse (e.g., for image processing, XML parsing, etc.) have known vulnerabilities that can be exploited to achieve Remote Code Execution (RCE).
        • How: Attackers identify vulnerable Python libraries used by Synapse. They then craft malicious input (e.g., specially crafted images, XML documents) that, when processed by Synapse using the vulnerable library, triggers the vulnerability and allows them to execute arbitrary code on the server.
  • 3.2. Synapse Configuration and Deployment Weaknesses [HR]:
    • 3.2.1. Misconfiguration of Synapse settings [HR]:
      • 3.2.1.1. Insecure default configurations left unchanged [HR]:
        • Attack Vector: Administrators fail to change insecure default settings in Synapse's configuration.
        • How: Attackers exploit well-known default credentials, overly permissive settings, or insecure features that are enabled by default in Synapse but should be hardened in a production environment.
      • 3.2.1.2. Overly permissive access controls or insecure feature enablement [HR]:
        • Attack Vector: Administrators misconfigure Synapse access controls, making them too permissive, or enable insecure features unnecessarily.
        • How: Attackers identify overly permissive access control settings (e.g., allowing anonymous access to sensitive APIs, granting excessive permissions to users). They exploit these misconfigurations to gain unauthorized access or perform actions they shouldn't be allowed to.
    • 3.2.2. Insecure Deployment Practices [HR]:
      • 3.2.2.1. Running Synapse with overly broad permissions [HR]:
        • Attack Vector: The Synapse server processes are run with overly broad operating system permissions (e.g., as root user).
        • How: If any vulnerability is exploited in Synapse (e.g., RCE), the impact is amplified because the Synapse process has excessive privileges. An attacker could gain full control of the server due to the broad permissions.
      • 3.2.2.2. Exposing unnecessary Synapse ports or services to the public internet [HR]:
        • Attack Vector: Unnecessary Synapse ports or services are exposed to the public internet, increasing the attack surface.
        • How: Attackers can target these exposed, unnecessary services for vulnerabilities. Even if the core Synapse API is secure, other exposed services might have weaknesses that can be exploited.
      • 3.2.2.3. Lack of proper network segmentation and firewall rules [HR]:
        • Attack Vector: The Synapse server is not properly segmented within the network and lacks adequate firewall rules.
        • How: If the Synapse server is compromised, the lack of segmentation and firewalls allows attackers to easily move laterally within the network to attack other systems and resources.
  • 3.3. Synapse Code Vulnerabilities (Bugs in Synapse itself) [CR]:
    • 3.3.1. Remote Code Execution (RCE) in Synapse Core [CR]:
      • 3.3.1.1. Exploiting vulnerabilities in Synapse's Python code to execute arbitrary code on the server [CR]:
        • Attack Vector: Vulnerabilities exist directly within Synapse's Python codebase that can be exploited to achieve Remote Code Execution (RCE).
        • How: Attackers discover and exploit bugs in Synapse's Python code. This could involve vulnerabilities in request handling, data processing, or any other part of the Synapse codebase. Successful exploitation allows them to execute arbitrary commands on the Synapse server, leading to full compromise.

Attack Tree Path: 4. Social Engineering and Phishing (Indirectly related to Synapse) [HR]

Attack Vector: Attackers use social engineering and phishing techniques to compromise user or administrator credentials, indirectly gaining access to the Synapse application.

• Breakdown:
  • 4.1. Compromise User Credentials [HR]:
    • 4.1.1. Phishing attacks targeting Synapse users to steal credentials [HR]:
      • 4.1.1.1. Spear phishing emails or messages mimicking Synapse login pages [HR]:
        • Attack Vector: Attackers send targeted phishing emails or messages to Synapse users, impersonating legitimate Synapse login pages or communications.
        • How: Attackers craft convincing phishing emails that appear to be from Synapse or related services. These emails typically contain links to fake login pages that look identical to the real Synapse login. Users who are tricked into entering their credentials on these fake pages have their usernames and passwords stolen by the attackers.
    • 4.1.2. Social engineering to obtain user credentials [HR]:
      • 4.1.2.1. Tricking users into revealing passwords or API keys [HR]:
        • Attack Vector: Attackers use various social engineering tactics to directly trick users into revealing their Synapse passwords or API keys.
        • How: Attackers might impersonate technical support, system administrators, or other trusted individuals. They use persuasive language and manipulation to convince users to disclose their credentials, often under false pretenses (e.g., claiming they need the password for account verification or troubleshooting).
    • 4.1.3. Credential reuse attacks if users use same passwords elsewhere [HR]:
      • 4.1.3.1. Exploiting leaked credentials from other services to access Synapse accounts [HR]:
        • Attack Vector: Users reuse the same passwords across multiple online services. If credentials for another service are leaked in a data breach, attackers can try to use those leaked credentials to access Synapse accounts.
        • How: Attackers obtain lists of leaked credentials from data breaches of other websites or services. They then use these leaked username/password combinations to attempt to log in to Synapse accounts, hoping that users have reused the same passwords.
  • 4.2. Compromise Admin Credentials [HR] [CR]:
    • 4.2.1. Phishing attacks targeting Synapse administrators [HR]:
      • 4.2.1.1. Spear phishing emails targeting admins with malicious attachments or links [HR]:
        • Attack Vector: Attackers specifically target Synapse administrators with spear phishing emails, often containing malicious attachments or links.
        • How: Attackers craft highly targeted phishing emails aimed at Synapse administrators. These emails might contain malicious attachments (e.g., malware-laden documents) or links to websites that attempt to install malware or steal credentials. If administrators are tricked into opening attachments or clicking links, their systems can be compromised, potentially leading to the theft of admin credentials.
    • 4.2.2. Social engineering to obtain admin credentials [HR]:
      • 4.2.2.1. Impersonating legitimate personnel to trick admins into revealing credentials [HR]:
        • Attack Vector: Attackers use sophisticated social engineering to impersonate trusted personnel (e.g., senior management, IT staff) to trick Synapse administrators into revealing their admin credentials.
        • How: Attackers carefully research the organization and identify individuals that administrators are likely to trust. They then impersonate these individuals, using phone calls, emails, or other communication methods to contact administrators and request their credentials under false pretenses (e.g., claiming an urgent system issue requires immediate admin access).
    • 4.2.3. Weak or default admin passwords [HR]:
      • 4.2.3.1. Exploiting default or easily guessable admin passwords if not changed [HR]:
        • Attack Vector: Synapse administrators fail to change default admin passwords or choose weak, easily guessable passwords.
        • How: Attackers attempt to log in to Synapse admin interfaces using default credentials (if they are known) or by trying common or easily guessable passwords. If default passwords are not changed or weak passwords are used, attackers can gain administrative access with minimal effort.