mcp-server-semgrep/semgrep-rules/go/lang/security/audit/xss/template-html-does-not-escape.yaml

MCP Server for Semgrep Integration - static code analysis with AI

rules:
- id: unsafe-template-type
  message: >-
    Semgrep could not determine that the argument to 'template.HTML()'
    is a constant. 'template.HTML()' and similar does not escape contents.
    Be absolutely sure there is no user-controlled data in this
    template. If user data can reach this template, you may have
    a XSS vulnerability. Instead, do not use this function and
    use 'template.Execute()'.
  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://golang.org/pkg/html/template/#HTML
    - https://github.com/0c34/govwa/blob/139693e56406b5684d2a6ae22c0af90717e149b8/vulnerability/xss/xss.go#L33
    category: security
    technology:
    - go
    confidence: LOW
    cwe2022-top25: true
    cwe2021-top25: true
    subcategory:
    - audit
    likelihood: LOW
    impact: MEDIUM
  languages: [go]
  severity: WARNING
  patterns:
  - pattern-not: template.$ANY("..." + "...")
  - pattern-not: template.$ANY("...")
  - pattern-either:
    - pattern: template.HTML(...)
    - pattern: template.CSS(...)
    - pattern: template.HTMLAttr(...)
    - pattern: template.JS(...)
    - pattern: template.JSStr(...)
    - pattern: template.Srcset(...)
    - pattern: template.URL(...)