# Insertion of Sensitive Information into Log File (CWE-532)

Information written to log files can be of a sensitive nature and give valuable guidance to an attacker or expose sensitive user information.

**Stack:** Python

- Prevalence: 中 3 言語をカバー
- Impact: ハイ 1 件の重大度ハイのルール
- Prevention: 文書化済み 3 件の修正例

**OWASP:** Security Logging and Monitoring Failures (A09:2021-Security Logging and Monitoring Failures) - #9

## Description

When sensitive information like passwords, tokens, or personal data is logged, it becomes accessible to anyone with access to the logs. Log files are often stored with less security than the data they contain.

## Prevention

1 件の Shoulder 検出ルールに基づく Information Exposure Through Logs の予防策。

### Python

Redact sensitive fields before logging; log actions and identifiers, not credentials

## Warning Signs

- [HIGH] logging of sensitive data like passwords, API keys, tokens, credit
cards, or authentication credenti

## Consequences

- アプリケーションデータの読み取り
- 権限の取得

## Mitigations

- パスワードやトークンなどの機密情報はログに記録しない
- ログデータの分類とフィルタリングを実装する
- ログに記録する前に機密データをマスクまたは伏字化する

## Detection

- Total rules: 3
- Languages: go, javascript, typescript, python

## Rules by Language

### Python (1 rules)

- **Sensitive Data in Logging** [HIGH]: Detects logging of sensitive data like passwords, API keys, tokens, credit
cards, or authentication credentials. Logged sensitive data can be exposed
through log files, monitoring systems, or error tracking services.
  - Remediation: Redact sensitive fields before logging; log actions and usernames, not credentials.

```python
import logging

logger = logging.getLogger(__name__)

SENSITIVE = {'password', 'token', 'api_key', 'secret'}

def sanitize(data):
    return {k: '***' if k in SENSITIVE else v for k, v in data.items()}

def login(username, password):
    logger.info(f"Login attempt for: {username}")  # Log username, not password
    authenticate(username, password)
```

Learn more: https://shoulder.dev/learn/python/cwe-532/sensitive-data-logging