attack-tree.md

Attack Tree Analysis for path/fastimagecache

Objective: To gain unauthorized access to sensitive data, disrupt service availability, or execute arbitrary code on the server by exploiting vulnerabilities in the fastimagecache library.

Attack Tree Visualization

                                      Compromise Application via fastimagecache
                                                    |
        ---------------------------------------------------------------------------------
        |                                               |
  ***1. Data Leakage/Exposure***              ***2. Denial of Service (DoS)***
        |                                               |
  -------------                                 ---------------------
  |           |                                 |                   |
***1.1***   !!!1.2!!!                       ***2.1***           ***2.2***
Cache       Unauth.                         Cache               Resource
Poisoning   Access to                       Poisoning (Fill)    Exhaustion
            Cached Data
            |
      ---------------
      |             |
  1.2.a Dir.    1.2.b Insuff.
  Traversal     Permissions
      |
  1.2.c Pred.
  Cache File
  Naming

Attack Tree Path: 1. Data Leakage/Exposure

• ***1.1 Cache Poisoning (Specific to Image Caching)***

  • Description: An attacker manipulates the caching mechanism to serve incorrect or malicious image data to legitimate users. This targets the image caching specifically.
  • How:
    • Exploiting vulnerabilities in how fastimagecache determines cache keys (e.g., insufficient validation of request headers, query parameters, or image metadata).
    • Bypassing cache validation mechanisms (e.g., forging valid image signatures or hashes).
    • Exploiting race conditions in the caching process.
  • Likelihood: Medium
  • Impact: High
  • Effort: Medium
  • Skill Level: Intermediate to Advanced
  • Detection Difficulty: Medium to Hard

• !!!1.2 Unauthorized Access to Cached Data!!!

  • Description: An attacker gains direct access to the cache storage and retrieves sensitive images or data.
  • How:
    • 1.2.a Directory Traversal: Using ../../ sequences to access files outside the intended cache directory.
      • Likelihood: Low
      • Impact: High
      • Effort: Low
      • Skill Level: Novice to Intermediate
      • Detection Difficulty: Medium
    • 1.2.b Insufficient Permissions: The cache directory or database has overly permissive access controls.
      • Likelihood: Low
      • Impact: High
      • Effort: Very Low
      • Skill Level: Novice
      • Detection Difficulty: Easy
    • 1.2.c Predictable Cache File Naming: The library uses predictable file names, allowing attackers to guess and access cached images directly.
      • Likelihood: Medium
      • Impact: Medium to High
      • Effort: Low to Medium
      • Skill Level: Intermediate
      • Detection Difficulty: Medium

Attack Tree Path: 2. Denial of Service (DoS)

• ***2.1 Cache Poisoning (Fill)***

  • Description: An attacker floods the cache with invalid or large images, consuming storage and evicting legitimate cached images.
  • How:
    • Exploiting weaknesses in cache size limits or eviction policies.
    • Generating many unique cache keys by manipulating request parameters.
  • Likelihood: Medium
  • Impact: Medium to High
  • Effort: Low to Medium
  • Skill Level: Intermediate
  • Detection Difficulty: Medium

• ***2.2 Resource Exhaustion***

  • Description: An attacker sends requests that consume excessive server resources (CPU, memory, network) during image processing or caching.
  • How:
    • Requesting extremely large images.
    • Exploiting vulnerabilities in image processing libraries (e.g., image bombs).
    • Triggering excessive disk I/O.
  • Likelihood: Medium
  • Impact: High
  • Effort: Low to Medium
  • Skill Level: Intermediate
  • Detection Difficulty: Medium