<!-- Copyright (c) 2026 defconxt. All rights reserved. -->
<!-- Licensed under AGPL-3.0 — see LICENSE file for details. -->
---
name: implementing-secure-file-operations
description: >-
  Implement safe file handling to prevent path traversal, symlink attacks, and unauthorized access.
domain: cybersecurity
subdomain: secure-coding
tags:
  - file-operations
  - path-traversal
  - symlink
  - secure-coding
version: "1.0"
author: defconxt
license: AGPL-3.0
metadata:
  mitre-attack: ["T1083"]
---

# Implementing Secure File Operations

## Overview

Implement safe file handling to prevent path traversal, symlink attacks, and unauthorized access.

## Prerequisites

| Requirement | Install |
|---|---|
| pathlib | Python path handling |
| OS hardening | File permissions |
| Python 3.10+ | For agent tooling |

## Key Concepts

Secure file ops prevent path traversal, symlink following, TOCTOU
race conditions, and permission issues. Always resolve paths.

## Quick Reference

```bash
from pathlib import Path; safe = Path(base).resolve() / filename
node agent.js scan --directory src/ --check file-operations
node agent.js audit --file upload.py --checks traversal,symlink
node agent.js fix --file upload.py --finding FILE-001
```

## Workflow

1. Use pathlib
2. Resolve and validate
3. Check symlinks
4. Restrictive permissions
5. Atomic operations
6. Content type validation
7. Audit file ops

## Detection

```yaml
title: Secure File Operations Detection
id: 25886329-157e-4b90-b994-289ba1bc19aa
status: experimental
description: Detects suspicious activity related to implementing secure file operations techniques in secure coding context
logsource:
  category: application
  product: webserver
detection:
  selection:
    EventType: error
  condition: selection
level: medium
tags:
  - attack.t1083
  - attack.initial_access
falsepositives:
  - Static analysis tools scanning source code repositories
```

## Verification

- Traversal prevented
- Symlink restricted
- Permissions set
- Atomic ops
- Content validated

## References

- OWASP Testing Guide — https://owasp.org/www-project-web-security-testing-guide/
- MITRE ATT&CK — https://attack.mitre.org/
- NIST SP 800-53 — https://csf.tools/reference/nist-sp-800-53/
