# Insecure Temporary File (CWE-377)

Creating and using insecure temporary files can leave application and system data vulnerable to attack.

- Prevalence: Moyenne 1 langages couverts
- Impact: Moyen Revue recommandée
- Prevention: Documentée 1 exemples de correctifs

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

## Description

Temporary files that are created with predictable names, insecure permissions, or in shared directories can be exploited by attackers to read or modify sensitive data, or to inject malicious content.

## Prevention

### Key Practices

- Use tempfile

### Python

Use tempfile.NamedTemporaryFile or tempfile.mkstemp instead of mktemp

## Warning Signs

- [MEDIUM] insecure temporary file creation using tempfile

## Consequences

- Lecture des données de l'application
- Modification des données de l'application
- Exécuter du code non autorisé

## Mitigations

- Utilisez des fonctions sécurisées de création de fichiers temporaires (par ex. mkstemp)
- Créez des fichiers temporaires dans des répertoires sûrs, non accessibles en écriture à tous
- Définissez des permissions restrictives sur les fichiers temporaires

## Detection

- Total rules: 1
- Languages: python

## Rules by Language

### Python (1 rules)

- **Insecure Temporary File Creation** [MEDIUM]: Detects insecure temporary file creation using tempfile.mktemp(), predictable
names, or world-readable permissions. These can lead to symlink attacks, race
conditions, or information disclosure. Use tempfile.mkstemp() or NamedTemporaryFile.
  - Remediation: Use tempfile.NamedTemporaryFile or tempfile.mkstemp instead of mktemp().

```python
import tempfile

with tempfile.NamedTemporaryFile(mode='w+', delete=True) as tmp:
    tmp.write(data)
    tmp.flush()
    result = process_file(tmp.name)
```

Learn more: https://shoulder.dev/learn/python/cwe-377/insecure-tempfile