Skip to content

Latest commit

 

History

History
49 lines (42 loc) · 4.67 KB

attack-surface.md

File metadata and controls

49 lines (42 loc) · 4.67 KB

Attack Surface Analysis for phpoffice/phppresentation

Attack Surface: Malicious Presentation File Upload (Parsing Vulnerabilities)

  • Description: The application allows users to upload presentation files processed by phpoffice/phppresentation. A malicious file can exploit parsing vulnerabilities within the library itself.
  • phppresentation Contribution: phpoffice/phppresentation is directly responsible for parsing complex presentation file formats. Vulnerabilities in its parsing logic create a direct pathway for exploitation.
  • Example: Uploading a crafted PPTX file that, when parsed by phpoffice/phppresentation, triggers a buffer overflow, leading to remote code execution on the server.
  • Impact:
    • Remote Code Execution (RCE) - Complete server compromise.
    • Denial of Service (DoS) - Application becomes unavailable.
    • Server-Side Request Forgery (SSRF) - Potential access to internal networks.
    • Information Disclosure - Leakage of sensitive server-side data.
  • Risk Severity: Critical
  • Mitigation Strategies:
    • Strict Input Validation: Validate file extensions and MIME types. Implement file size limits.
    • Sandboxing: Process file parsing in isolated environments (containers, sandboxes) to limit exploit impact.
    • Regular Updates: Keep phpoffice/phppresentation and dependencies updated to patch known vulnerabilities.
    • Vulnerability Scanning: Regularly scan phpoffice/phppresentation and dependencies for vulnerabilities.

Attack Surface: File Format Vulnerabilities (Parsing Logic Flaws)

  • Description: Presentation file formats are intricate. Flaws in phpoffice/phppresentation's parsing implementation for specific file structures can be exploited.
  • phppresentation Contribution: The core function of phpoffice/phppresentation is parsing these complex formats. Parsing logic vulnerabilities are inherent to the library's operation.
  • Example: A PPTX file with a malformed XML structure triggers an XML External Entity (XXE) vulnerability in phpoffice/phppresentation's XML parsing, allowing an attacker to read local files on the server.
  • Impact:
    • Information Disclosure - Reading sensitive server files.
    • Denial of Service (DoS) - Application crash due to parsing errors.
    • Potential Remote Code Execution (RCE) - Depending on vulnerability specifics.
  • Risk Severity: High to Critical (depending on vulnerability type and exploitability)
  • Mitigation Strategies:
    • Secure XML Parsing Configuration: Securely configure XML parsing libraries used by phpoffice/phppresentation, disabling external entity resolution if unnecessary.
    • Regular Updates: Keep phpoffice/phppresentation updated for parsing logic bug fixes and security patches.
    • Fuzzing and Security Testing: Conduct thorough fuzzing and security testing of file parsing with malformed and edge-case files.
    • Code Audits: Perform code audits of phpoffice/phppresentation's parsing logic to identify potential flaws.

Attack Surface: Resource Exhaustion (DoS) through File Processing

  • Description: Processing large or complex presentation files using phpoffice/phppresentation can consume excessive server resources, leading to Denial of Service.
  • phppresentation Contribution: phpoffice/phppresentation performs the resource-intensive task of file parsing and manipulation. Inefficient processing or lack of resource limits when using the library directly contributes to this risk.
  • Example: An attacker repeatedly uploads very large PPTX files or files with numerous slides and complex elements. phpoffice/phppresentation's processing of these files exhausts server CPU and memory, causing application unresponsiveness.
  • Impact:
    • Denial of Service (DoS) - Application becomes unavailable or severely degraded for legitimate users.
  • Risk Severity: High
  • Mitigation Strategies:
    • Resource Limits: Implement PHP resource limits (memory, execution time) for file processing.
    • Rate Limiting: Implement rate limits on file upload and processing endpoints to prevent abuse.
    • Asynchronous Processing: Offload file processing to background queues to prevent blocking the main application thread.
    • File Size and Complexity Limits: Enforce reasonable file size limits and potentially limits on presentation complexity.