Skip to content

Latest commit

 

History

History
29 lines (24 loc) · 4.36 KB

threat-modeling.md

File metadata and controls

29 lines (24 loc) · 4.36 KB

Threat Model Analysis for serbanghita/mobile-detect

Threat: User-Agent Spoofing for Critical Access Bypass (Misuse Scenario)

Description: An attacker manipulates their browser's User-Agent string to impersonate an authorized device type (e.g., mobile device in a mobile-only application). This is possible because the application mistakenly relies solely on mobile-detect for critical access control or authentication decisions. By spoofing the User-Agent, the attacker bypasses these flawed security checks and gains unauthorized access to sensitive resources or functionalities intended only for specific device types. For example, accessing administrative panels or sensitive data meant only for "trusted" mobile devices, simply by changing the User-Agent from a desktop browser.

  • Impact: Critical. Complete bypass of intended access control mechanisms. Unauthorized access to sensitive data, administrative functions, or restricted areas of the application. Potential for data breaches, system compromise, and significant business impact if critical security relies on device detection.
  • Mobile-detect component affected: Core detection logic, getUa(), device type detection methods (e.g., isMobile(), isTablet(), isDesktop()) when misused for security.
  • Risk severity: Critical (when misused for security)
  • Mitigation strategies:
    • Absolutely avoid using mobile-detect or any User-Agent based detection for critical access control, authentication, or authorization.
    • Implement robust, server-side security measures that are independent of client-provided User-Agent strings. Use established authentication and authorization protocols (e.g., OAuth 2.0, JWT, session-based authentication) and role-based access control.
    • Treat device detection solely as a mechanism for user experience enhancement and progressive enhancement, not security enforcement.
    • Educate developers about the security limitations of User-Agent based device detection and the dangers of relying on it for security.

Threat: Regular Expression Denial of Service (ReDoS) - High Impact Scenario

Description: An attacker crafts and sends a highly specific User-Agent string designed to exploit inefficient regular expressions within the mobile-detect library. This malicious User-Agent triggers excessive backtracking in the regex engine during processing. This leads to a significant consumption of server CPU and memory resources, potentially causing a Denial of Service (DoS) condition. If successful, the server becomes unresponsive or crashes, impacting availability for all legitimate users. The impact is amplified if the application processes User-Agent strings on every request and lacks proper DoS protection.

  • Impact: High. Server-side Denial of Service, application unavailability, significant disruption of service for all users. Potential financial losses and reputational damage due to prolonged downtime.
  • Mobile-detect component affected: Regular expressions used for User-Agent parsing and device signature matching within the core detection logic.
  • Risk severity: High (potential for significant service disruption)
  • Mitigation strategies:
    • Immediately update mobile-detect library to the latest version. Developers may have addressed ReDoS vulnerabilities in newer releases by optimizing regular expressions or implementing safeguards.
    • Implement robust server-level Denial of Service (DoS) protection measures. This includes:
      • Rate limiting: Limit the number of requests from a single IP address within a given timeframe.
      • Request timeouts: Set timeouts for request processing to prevent long-running regex operations from monopolizing resources.
      • Web Application Firewall (WAF): A WAF can help identify and block malicious requests, including those designed to trigger ReDoS.
    • Monitor server resource utilization (CPU, memory) closely. Set up alerts to detect unusual spikes that could indicate a ReDoS attack in progress.
    • Consider using alternative, more robust User-Agent parsing libraries or methods that are less susceptible to ReDoS if DoS attacks become a recurring concern.