mcp-server-semgrep/semgrep-rules/python/django/security/audit/xss/formathtml-fstring-parameter.yaml

MCP Server for Semgrep Integration - static code analysis with AI

rules:
- id: formathtml-fstring-parameter
  message: >-
    Passing a formatted string as first parameter to `format_html` disables the
    proper encoding of variables. Any HTML in the first parameter is not
    encoded. Using a formatted string as first parameter obscures which
    parameters are encoded. Correct use of `format_html` is passing a static
    format string as first parameter, and the variables to substitute as
    subsequent parameters.
  metadata:
    cwe:
    - "CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')"
    owasp:
    - A07:2017 - Cross-Site Scripting (XSS)
    - A03:2021 - Injection
    references:
    - https://docs.djangoproject.com/en/3.2/ref/utils/#django.utils.html.format_html
    category: security
    technology:
    - django
    cwe2022-top25: true
    cwe2021-top25: true
    subcategory:
    - audit
    likelihood: LOW
    impact: MEDIUM
    confidence: LOW
  languages:
  - python
  severity: WARNING
  pattern-either:
  - pattern: format_html(<... f"..." ...>, ...)
  - pattern: format_html("..." % ..., ...)
  - pattern: format_html("...".format(...), ...)