mcp-server-semgrep/semgrep-rules/csharp/lang/security/injections/os-command.yaml

MCP Server for Semgrep Integration - static code analysis with AI

rules:
- id: os-command-injection
  severity: ERROR
  languages:
  - csharp
  metadata:
    cwe:
    - "CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')"
    owasp:
    - A01:2017 - Injection
    - A03:2021 - Injection
    references:
    - https://owasp.org/www-community/attacks/Command_Injection
    category: security
    technology:
    - .net
    confidence: LOW
    cwe2022-top25: true
    cwe2021-top25: true
    subcategory:
    - audit
    likelihood: LOW
    impact: HIGH
  message: >-
    The software constructs all or part of an OS command using externally-influenced input from an upstream
    component, but
    it does not neutralize or incorrectly neutralizes special elements that could modify the intended
    OS command when it is
    sent to a downstream component.
  patterns:
  - pattern-inside: |
      using System.Diagnostics;
      ...
  - pattern-inside: |
      public $T $F(..., $ARG, ...)
      {
        ...
      }
  - pattern-either:
    - patterns:
      - pattern: |
          Process.Start($ARG, ...);
      - focus-metavariable: $ARG
    - patterns:
      - pattern-inside: |
          Process $PROC = new Process();
          ...
      - pattern-either:
        - pattern-inside: |
            $PROC.StartInfo.FileName = $ARG;
            ...
        - pattern-inside: |
            $PROC.StartInfo.Arguments = <... $ARG ...>;
            ...
      - pattern: |
          $PROC.Start();
    - patterns:
      - patterns:
        - pattern-inside: |
            ProcessStartInfo $PSINFO = new ProcessStartInfo()
            {
              ...
            };
            ...
        - pattern-either:
          - pattern-inside: |
              FileName = $ARG;
              ...
          - pattern-inside: |
              Arguments = <... $ARG ...>;
              ...
      - pattern: |
          Process.Start($PSINFO);
      - focus-metavariable: $PSINFO
    - patterns:
        - pattern-inside: |
            Process $PROC = new Process()
            {
              StartInfo = new ProcessStartInfo()
              {
                ...
              }
            };
            ...
        - pattern-either:
            - pattern-inside: |
                FileName = $ARG;
                ...
            - pattern-inside: |
                Arguments = $ARG;
                ...
        - pattern: |
            $PROC.Start();