# Generation of Error Message Containing Sensitive Information (CWE-209)

The product generates an error message that includes sensitive information about its environment, users, or associated data.

**Stack:** Python

- Prevalence: Media 3 lenguajes cubiertos
- Impact: Medio Se recomienda revisión
- Prevention: Documentada 5 ejemplos de corrección

**OWASP:** Insecure Design (A04:2021-Insecure Design) - #4

## Description

The sensitive information may be valuable information on its own, or it may be useful for launching other, more serious attacks. The error message may be created in different ways, and the information that is included can range widely.

## Prevention

Estrategias de prevención para Error Message Information Leak basadas en 2 reglas de detección de Shoulder.

### Python

Log full exception details internally but return generic error messages to users

Return generic responses; log internal paths server-side only

## Warning Signs

- [MEDIUM] error messages that expose sensitive implementation details like
stack traces, database errors, file
- [MEDIUM] responses that include internal file paths, IP addresses, or system
information

## Consequences

- Leer datos de la aplicación
- Leer archivos o directorios

## Mitigations

- Maneja las excepciones internamente y no muestres errores al usuario
- Crea páginas de error predeterminadas para errores HTTP como 404 y 500
- Implementa un manejo de errores adecuado que registre los detalles en el servidor pero muestre mensajes genéricos a los usuarios

## Detection

- Total rules: 5
- Languages: go, javascript, typescript, python

## Rules by Language

### Python (2 rules)

- **Error Message Information Disclosure** [MEDIUM]: Detects error messages that expose sensitive implementation details like
stack traces, database errors, file paths, or internal system information.
This information can help attackers understand the system architecture.
  - Remediation: Log full exception details internally but return generic error messages to users.

```python
import logging
from flask import jsonify

logger = logging.getLogger(__name__)

@app.route('/api/data')
def get_data():
    try:
        return jsonify(process_data())
    except Exception as e:
        logger.error(f"Processing failed: {e}", exc_info=True)
        return jsonify({'error': 'Internal server error'}), 500
```

Learn more: https://shoulder.dev/learn/python/cwe-209/error-message-exposure
- **Internal Path and IP Address Disclosure** [MEDIUM]: Detects responses that include internal file paths, IP addresses, or system
information. This information helps attackers understand the system architecture,
file structure, and internal network topology.
  - Remediation: Return generic error messages; log internal details without exposing them in responses.

```python
import logging
from flask import jsonify

logger = logging.getLogger(__name__)

@app.route('/info')
def get_info():
    logger.info(f"Request to {__file__}")  # Log internally
    return jsonify({'status': 'ok', 'version': '1.0'})  # Generic response
```

Learn more: https://shoulder.dev/learn/python/cwe-209/internal-path-disclosure