# Security Audit Report — GuardDog Nexus

**Date:** 2026-05-10  
**Auditor:** Automated security audit  
**Last updated:** 2026-05-11  
**Scope:** Full codebase review — security vulnerabilities, logic errors, missing controls

---

## Summary

| Severity | Count | Fixed | Rejected | Remaining |
|----------|-------|-------|----------|-----------|
| CRITICAL | 5     | 2     | 2        | 1         |
| HIGH     | 7     | 2     | 3        | 2         |
| MEDIUM   | 8     | 3     | 0        | 5         |
| LOW      | 6     | 2     | 0        | 4         |
| **Total**| **26**| **9** | **5**    | **12**    |

---

## CRITICAL (5)

### C1. SSRF via webhook downloadUrl ✅ FIXED
**Severity:** CRITICAL  
**Fix:** `NEXUS_ALLOWED_HOSTS` env var + `_validate_download_url()` in `core/nexus.py`.

**Problem:** `downloadUrl` из webhook-пэйлода передаётся напрямую в `httpx.AsyncClient.get()` без валидации.

```python
download_url = asset.get("downloadUrl") or _build_download_url(repository, asset_path)
# ...
response = await client.get(download_url)  # no validation
```

**Real-world impact:** Атакующий отправляет webhook с `downloadUrl: "http://169.254.169.254/latest/meta-data/iam/security-credentials/"` → сервер скачивает IAM-учётные данные облака.

**Fix:** Validate URL scheme (http/https only), block private IP ranges (10.x, 172.16.x, 192.168.x, 127.x, 169.254.x, ::1), optionally whitelist domain against `config.nexus_url`.

---

### C2. Webhook secret not enforced by default ❌ ACCEPTED RISK
**Severity:** CRITICAL  
**Decision:** Внутренний сервис, секрет опционален.

---

### C3. Default admin credentials ✅ FIXED
**Severity:** CRITICAL  
**Fix:** Убран BasicAuth из всех запросов к Nexus (анонимный доступ).

---

### C4. XSS via LLM report verdict ❌ NOT DANGEROUS
**Severity:** CRITICAL — downgraded to INFO  
**Decision:** Jinja2 autoescape блокирует инъекцию в атрибутах.

---

### C5. LLM Prompt Injection ⚠️ PARTIALLY MITIGATED
**Severity:** CRITICAL  
**Mitigation:** System prompt gives priority to system instructions. Raw finding data still in user message.

---

## HIGH (7)

### H1. No rate limiting ❌ REJECTED
### H2. Path traversal ⚠️ LOW RISK
**Severity:** HIGH — downgraded  
**Analysis:** `os.path.basename("../../../etc/passwd")` → `"passwd"`, traversal невозможен.

---

### H3. Sensitive data in API ❌ REJECTED (source_ip is a feature)
### H4. No authentication ❌ REJECTED (internal service)
### H5. Memory leak in locks ✅ FIXED (bg cleanup every 30min)
### H6. Race condition in URL locking ✅ FIXED (DB re-check inside lock)
### H7. CSV export bounded ❌ REJECTED (acceptable for internal tool)

---

## MEDIUM (8)

### M1. No LLM response schema validation
**Severity:** MEDIUM  
**File:** `core/llm.py:80-82`

**Problem:** LLM response parsed as JSON but not validated against schema. Missing `report.verdict` → Jinja2 renders empty string → CSS broken.

**Fix:** Pydantic model для валидации LLM response.

---

### M2. No CSRF protection
**Severity:** MEDIUM  
**File:** `routes/web.py:205-274`

**Problem:** POST `/api/v1/findings/{id}/analyze` без CSRF token.

**Fix:** Добавить CSRF token для всех POST endpoints.

---

### M3. No security headers
**Severity:** MEDIUM  
**File:** `main.py`

**Problem:** Отсутствие CSP, X-Content-Type-Options, X-Frame-Options, X-XSS-Protection.

**Fix:** Middleware для security headers.

---

### M4. SQLite without WAL mode
**Severity:** MEDIUM  
**File:** `db/engine.py:12`

**Problem:** Concurrent readers block writers → poor performance under load.

**Fix:** `PRAGMA journal_mode=WAL` in connection setup.

---

### M5. Scoped npm packages not supported
**Severity:** MEDIUM  
**File:** `core/nexus.py:54-70`

**Problem:** `extract_npm_info` returns `None` для `@scope/package` → пропускаются сканирования.

**Fix:** Обновить extractor для scoped packages.

---

### M6. Dashboard stats — potential IndexError
**Severity:** MEDIUM  
**File:** `routes/api_scans.py:145-147`

**Problem:** `dashboard["latest_flagged"][0]` — IndexError если `latest_flagged` пустой.

```python
"latest_scan_at": dashboard["latest_flagged"][0].started_at.isoformat()
```

**Fix:** Guard с `if dashboard.get("latest_flagged")`.

---

### M7. Error message HTML escaping
**Severity:** MEDIUM  
**File:** `web/templates/scan_detail.html:30`

**Problem:** `scan.error_message` rendered в template — если содержит HTML/JS, может сломать UI.

**Fix:** Jinja2 autoescape handles this, но стоит добавить explicit escaping для `code` fields.

---

### M8. Unknown ecosystem defaults to pypi ✅ FIXED
**Severity:** MEDIUM  
**Fix:** `_detect_ecosystem()` возвращает `None` → webhook reject с `"unknown_ecosystem"`.  
**Duplicate:** L6.

---

## LOW (6)

### L1. Dockerfile grep hack ✅ FIXED (`uv pip install . --system`)
### L2. Health check without DB ✅ FIXED (`/health/dependencies`)

---

### L3. No backup strategy for SQLite
**Severity:** LOW  
**Risk:** Crash → corrupted database → data loss.

**Fix:** Регулярные backups через cron или switch to PostgreSQL for production.

---

### L4. Dead code — `parse_package_path` unused in harvester
**Severity:** LOW  
**File:** `core/nexus.py:93-99`

**Problem:** Функция определена но не используется в harvester pipeline.

**Fix:** Убрать или интегрировать.

---

### L5. Hardcoded LLM API base URL
**Severity:** LOW  
**File:** `constants.py:139`

**Problem:** Default `https://api.openai.com/v1` — unexpected API calls для пользователей локальных моделей.

**Fix:** Better default или warning at startup.

---

### L6. Unknown ecosystem defaults to pypi (webhook)
**Severity:** LOW  
**File:** `routes/webhooks.py:62`

**Problem:** Неизвестный format → fallback к pypi. Maven/NuGet webhooks будут сканироваться как PyPI пакеты.

**Fix:** Явно reject неизвестные ecosystems.

---

## Implementation Plan

### Phase 1 — P0 (Critical)

| # | Task | Status |
|---|------|--------|
| 1 | SSRF protection | ✅ FIXED |
| 2 | Mandatory WEBHOOK_SECRET | ❌ ACCEPTED |
| 3 | Remove default Nexus credentials | ✅ FIXED |
| 4 | LLM verdict whitelist + prompt injection | ⚠️ PARTIAL |
| 5 | Path traversal fix | ⚠️ LOW RISK |

### Phase 2 — P1 (High)

| # | Task | Status |
|---|------|--------|
| 6 | Rate limiting | ❌ REJECTED |
| 7 | API authentication | ❌ REJECTED |
| 8 | Memory leak fix for locks | ✅ FIXED |
| 9 | Race condition fix | ✅ FIXED |
| 10 | Remove source_ip from public API | ❌ REJECTED |
| 11 | CSV export auth + limit | ❌ REJECTED |

### Phase 3 — P2 (Medium)

| # | Task | Status |
|---|------|--------|
| 12 | LLM response validation (Pydantic) | ⬜ |
| 13 | CSRF protection | ⬜ |
| 14 | Security headers middleware | ⬜ |
| 15 | SQLite WAL mode | ⬜ |
| 16 | Scoped npm support | ⬜ |
| 17 | Dashboard None guard | ⬜ |
| 18 | `serialize_finding` вместо `**f.data` | ✅ FIXED |
| 19 | `_scan_component` try/except | ✅ FIXED |
| 20 | Reject unknown ecosystem | ✅ FIXED |

### Phase 4 — P3 (Low)

| # | Task | Status |
|---|------|--------|
| 21 | Dockerfile deps | ✅ FIXED |
| 22 | Health check DB ping | ✅ FIXED |
| 23 | Backup strategy docs | ⬜ |
| 24 | Reject unknown ecosystems | ✅ FIXED (duplicate) | |

---

## Test Coverage Gaps

The existing 85 tests do NOT cover:

- [ ] SSRF prevention (malicious downloadUrl)
- [ ] Webhook signature validation with empty secret
- [ ] Path traversal in download URLs
- [ ] Rate limiting on webhook endpoint
- [ ] Authentication on API endpoints
- [ ] LLM prompt injection
- [ ] LLM response schema validation
- [ ] CSRF protection
- [ ] Security headers presence
- [ ] Memory leak in lock dictionaries
- [ ] Race condition in URL locking
- [ ] Scoped npm package extraction
- [ ] Dashboard IndexError on empty data

---

## Recommendations

1. **Immediate:** Implement C1-C5 before any production deployment
2. **Short-term:** Implement H1-H7 within first sprint
3. **Medium-term:** Implement M1-M8 within first month
4. **Long-term:** Implement L1-L6 during routine maintenance
5. **Ongoing:** Add security-focused tests for all findings above