mcp-server-semgrep/semgrep-rules/go/lang/security/audit/net/formatted-template-string.yaml

MCP Server for Semgrep Integration - static code analysis with AI

rules:
- id: formatted-template-string
  message: >-
    Found a formatted template string passed to 'template.HTML()'. 'template.HTML()' 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.
  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
    category: security
    technology:
    - go
    confidence: MEDIUM
    cwe2022-top25: true
    cwe2021-top25: true
    subcategory:
    - audit
    likelihood: LOW
    impact: MEDIUM
  languages: [go]
  severity: WARNING
  patterns:
  - pattern-not: template.HTML("..." + "...")
  - pattern-either:
    - pattern: template.HTML($T + $X, ...)
    - pattern: template.HTML(fmt.$P("...", ...), ...)
    - pattern: |
        $T = "..."
        ...
        $T = $FXN(..., $T, ...)
        ...
        template.HTML($T, ...)
    - pattern: |
        $T = fmt.$P("...", ...)
        ...
        template.HTML($T, ...)
    - pattern: |
        $T, $ERR = fmt.$P("...", ...)
        ...
        template.HTML($T, ...)
    - pattern: |
        $T = $X + $Y
        ...
        template.HTML($T, ...)
    - pattern: |-
        $T = "..."
        ...
        $OTHER, $ERR = fmt.$P(..., $T, ...)
        ...
        template.HTML($OTHER, ...)