mcp-server-semgrep/semgrep-rules/ruby/rails/security/audit/xxe/libxml-backend.yaml

MCP Server for Semgrep Integration - static code analysis with AI

rules:
- id: libxml-backend
  languages: [ruby]
  pattern: ActiveSupport::XmlMini.backend = "LibXML"
  severity: WARNING
  message: >-
    This application is using LibXML as the XML backend. LibXML can be vulnerable to
    XML External Entities (XXE) vulnerabilities. Use the built-in Rails XML parser, REXML,
    instead.
  metadata:
    references:
    - https://www.stackhawk.com/blog/rails-xml-external-entities-xxe-guide-examples-and-prevention/
    - https://cheatsheetseries.owasp.org/cheatsheets/XML_External_Entity_Prevention_Cheat_Sheet.html
    technology:
    - rails
    - libxml
    category: security
    cwe:
    - 'CWE-611: Improper Restriction of XML External Entity Reference'
    owasp:
    - A04:2017 - XML External Entities (XXE)
    - A05:2021 - Security Misconfiguration
    confidence: LOW
    cwe2022-top25: true
    cwe2021-top25: true
    subcategory:
    - audit
    likelihood: LOW
    impact: MEDIUM