rules:
- id: template-href-var
  message: >-
    Detected a template variable used in an anchor tag with
    the 'href' attribute. This allows a malicious actor to
    input the 'javascript:' URI and is subject to cross-
    site scripting (XSS) attacks. Use the 'url' template tag
    to safely generate a URL. You may also consider setting
    the Content Security Policy (CSP) header.
  metadata:
    cwe: "CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')"
    owasp: 'A7: Cross-Site Scripting (XSS)'
    references:
    - https://flask.palletsprojects.com/en/1.1.x/security/#cross-site-scripting-xss
    - https://docs.djangoproject.com/en/3.1/ref/templates/builtins/#url
    - https://content-security-policy.com/
    category: security
    technology:
    - django
  languages:
  - regex
  paths:
    include:
    - '*.html'
  severity: WARNING
  pattern-regex: |-
    .*href\s*=\s*[\"\']?{{\s*.*