mcp-server-semgrep/semgrep-rules/python/lang/security/audit/dangerous-os-exec-audit.yaml

MCP Server for Semgrep Integration - static code analysis with AI

rules:
- id: dangerous-os-exec-audit
  message: >-
    Found dynamic content when spawning a process. This is dangerous if external
    data can reach this function call because it allows a malicious actor to
    execute commands. Ensure no external data reaches here.
  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://semgrep.dev/docs/cheat-sheets/python-command-injection/
    asvs:
      section: 'V5: Validation, Sanitization and Encoding Verification Requirements'
      control_id: 5.3.8 OS Command Injection
      control_url: https://github.com/OWASP/ASVS/blob/master/4.0/en/0x13-V5-Validation-Sanitization-Encoding.md#v53-output-encoding-and-injection-prevention-requirements
      version: '4'
    category: security
    technology:
    - python
    confidence: LOW
    cwe2022-top25: true
    cwe2021-top25: true
    subcategory:
    - audit
    likelihood: LOW
    impact: HIGH
  languages: [python]
  severity: ERROR
  pattern-either:
  - patterns:
    - pattern-not: os.$METHOD("...", ...)
    - pattern: os.$METHOD(...)
    - metavariable-regex:
        metavariable: $METHOD
        regex: (execl|execle|execlp|execlpe|execv|execve|execvp|execvpe)
  - patterns:
    - pattern-not: os.$METHOD("...", [$PATH,"...","...",...],...)
    - pattern: os.$METHOD($BASH,[$PATH,"-c",$CMD,...],...)
    - metavariable-regex:
        metavariable: $METHOD
        regex: (execv|execve|execvp|execvpe)
    - metavariable-regex:
        metavariable: $BASH
        regex: (.*)(sh|bash|ksh|csh|tcsh|zsh)
  - patterns:
    - pattern-not: os.$METHOD("...", $PATH, "...", "...",...)
    - pattern: os.$METHOD($BASH, $PATH, "-c", $CMD,...)
    - metavariable-regex:
        metavariable: $METHOD
        regex: (execl|execle|execlp|execlpe)
    - metavariable-regex:
        metavariable: $BASH
        regex: (.*)(sh|bash|ksh|csh|tcsh|zsh)