attack-tree.md

Attack Tree Analysis for bookstackapp/bookstack

Objective: To gain unauthorized access to sensitive information stored within BookStack, or to disrupt the availability of the BookStack service, by exploiting BookStack-specific vulnerabilities.

Attack Tree Visualization

                                     +-----------------------------------------------------+
                                     |  Gain Unauthorized Access/Disrupt BookStack Service  |
                                     +-----------------------------------------------------+
                                                        |
         +--------------------------------+-------------------------------+-------------------------------+
         |                                |                               |                               |
+------------+-----------+       +-----------+-----------+       +-----------+-----------+
| Exploit Authentication |       | Exploit  Input      |       | Exploit  Dependency  |
|       Bypass          |       |   Validation/      |       |    Vulnerabilities   |
+------------+-----------+       |    Sanitization     |       +-----------+-----------+
         |                               |                               |
         |                               |                               |
+------------+-----------+       +-----------+-----------+       +-----------+-----------+
| Weak/Default Password |       |  XSS (Stored)      |       |  Vulnerable BookStack|
|       Policy  {CRITICAL}|       |  in Attachments    |       |       Version         |
+------------+-----------+       +-----------+-----------+       +-----------+-----------+
         |                               |
         |                               |
+------------+-----------+
|  Brute-Force Attack   |
|       on Login        |
+------------+-----------+

Attack Tree Path: Exploit Authentication Bypass

1. Exploit Authentication Bypass:

   • Weak/Default Password Policy {CRITICAL}:

     • Description: BookStack's password policy allows users to set weak passwords (short, common, easily guessed) or the default password remains unchanged after installation.
     • Likelihood: Medium (Depends on administrator diligence.)
     • Impact: High (Direct access to user accounts.)
     • Effort: Low (If weak passwords are allowed, cracking is easy.)
     • Skill Level: Low (Basic password cracking techniques.)
     • Detection Difficulty: Medium (Failed login attempts might be logged, but successful brute-forcing might not be immediately obvious.)
     • Mitigation: Enforce a strong password policy (minimum length, complexity requirements, password history).

   • Brute-Force Attack on Login:

     • Description: Attackers repeatedly try different username/password combinations to gain access. This is successful if BookStack lacks rate limiting or account lockout mechanisms.
     • Likelihood: Medium (Depends on the presence of protective measures.)
     • Impact: High (Direct access to user accounts.)
     • Effort: Low to Medium (Automated tools are readily available.)
     • Skill Level: Low (Basic scripting and use of brute-forcing tools.)
     • Detection Difficulty: Medium to High (Depends on logging and intrusion detection.)
     • Mitigation: Implement rate limiting (limit login attempts per IP/user) and account lockout (temporarily disable accounts after multiple failed attempts).

Attack Tree Path: Exploit Input Validation/Sanitization

2. Exploit Input Validation/Sanitization:

   • XSS (Stored) in Attachments:
     • Description: Attackers upload files (e.g., HTML, SVG) containing malicious JavaScript. When other users view the attachment within BookStack, the script executes, potentially stealing cookies, hijacking sessions, or defacing content. This exploits BookStack's attachment handling.
     • Likelihood: Medium (Depends on BookStack's handling of attachments and content types.)
     • Impact: Medium to High (Compromising user accounts, stealing cookies, defacing content.)
     • Effort: Medium (Crafting a malicious attachment requires some knowledge.)
     • Skill Level: Medium (Requires understanding of XSS and file upload vulnerabilities.)
     • Detection Difficulty: Medium (Requires monitoring for unusual JavaScript execution and potentially analyzing uploaded files.)
     • Mitigation:
       • Strictly validate and sanitize all uploaded files.
       • Restrict allowed file types to only those necessary.
       • Use a content security policy (CSP) to limit the execution of scripts.
       • Serve attachments with a Content-Disposition: attachment header to force download instead of inline rendering.
       • Consider using a file type detection library, and do not rely solely on file extensions.

Attack Tree Path: Exploit Dependency Vulnerabilities

3. Exploit Dependency Vulnerabilities:

   • Vulnerable BookStack Version:
     • Description: Attackers exploit known vulnerabilities in a specific, outdated version of BookStack. Exploit code is often publicly available.
     • Likelihood: Medium (Depends on how quickly users update.)
     • Impact: Low to High (Depends on the specific vulnerability.)
     • Effort: Low to Medium (Exploiting known vulnerabilities is often straightforward.)
     • Skill Level: Low to Medium (Often, exploit code is publicly available.)
     • Detection Difficulty: Medium (Requires vulnerability scanning and version checking.)
     • Mitigation: Regularly update BookStack to the latest stable version. Subscribe to security advisories for BookStack.