# Security Testing Status

Tracking security testing progress and remaining tasks.

---

## Completed Testing

### Local Fuzzer (tests/fuzz/run_fuzz.py)

| Phase | Tests | Status |
|-------|-------|--------|
| Reconnaissance | 25 endpoints probed | PASS |
| Input Fuzzing | Binary, unicode, size limits | PASS |
| Injection Attacks | SQLi, XSS, SSTI, command injection | PASS |
| Auth/Authz | Header spoofing, privilege escalation | PASS |
| Business Logic | Burn-after-read, expiry, dedup | PASS |
| Cryptography | PoW token replay, timing | PASS |

### Production Fuzzer (mymx.me/paste)

| Phase | Tests | Status |
|-------|-------|--------|
| Content Fuzzing | Null bytes, unicode, 50KB, control chars | PASS |
| Injection Testing | SQLi, SSTI, XSS, command, path traversal | PASS |
| Header Injection | Host override, XFF chains, SQLi in headers | PASS |
| Path Fuzzing | Traversal, URL encoding, long paths | PASS |
| MIME Detection | GIF+JS, PNG+HTML, PDF+HTML polyglots | PASS |

### MIME Detection (Polyglot Attacks)

| Attack Vector | Payload | Result |
|---------------|---------|--------|
| PNG + HTML | Magic bytes + script tag | Served as image/png |
| GIF + JavaScript | GIF89a + JS comment trick | Served as image/gif |
| PDF + ZIP | PDF header + ZIP trailer | Served as application/pdf |
| SVG + Script | XML with embedded script | Served as text/plain |
| JPEG + PHP | JFIF + PHP code | Served as image/jpeg |

### Race Condition Testing

| Test | Method | Result |
|------|--------|--------|
| Burn-after-read bypass | HEAD then GET | SAFE - HEAD triggers deletion |

Verified via server logs: `Burn-after-read paste deleted via HEAD: <id>`

### Timing Attack Analysis

Tested authentication endpoints for timing oracle vulnerabilities (2025-12-25):

| Endpoint | Test | Variance | Result |
|----------|------|----------|--------|
| Password verification | Correct vs Wrong | 2.3% | SAFE |
| Password verification | Correct vs None | 2.1% | SAFE |
| Paste existence | Valid vs Invalid ID | Expected | OK (DB lookup) |
| Auth header | Valid vs Invalid format | Expected | OK (DB lookup) |

Password verification uses PBKDF2 with 600,000 iterations (~900ms constant-time).
No password oracle vulnerability - timing variance within acceptable bounds.

---

## Remaining Tasks

### MIME Detection - Additional Formats

Tested on production (2025-12-25):

```
[x] WebP (image/webp)                 PASS
[x] TIFF-LE (image/tiff)              PASS
[x] TIFF-BE (image/tiff)              PASS
[x] BMP (image/bmp)                   PASS
[x] ICO (image/x-icon)                PASS
[x] WebM (video/webm)                 PASS
[x] MP4 (video/mp4)                   PASS
[x] MP3 (audio/mpeg)                  PASS
[x] MP3-ID3 (audio/mpeg)              PASS
[x] FLAC (audio/flac)                 PASS
[x] OGG (audio/ogg)                   PASS
[x] 7z (application/x-7z-compressed)  PASS
[x] RAR (application/vnd.rar)         PASS
[x] XZ (application/x-xz)             PASS
[x] BZ2 (application/x-bzip2)         PASS
[x] WASM (application/wasm)           PASS
[x] MachO-32 (application/x-mach-binary) PASS
[x] MachO-64 (application/x-mach-binary) PASS

Fallback to text/plain (safe default):
[~] MOV  - ftyp offset varies
[~] CAB  - Signature not implemented
[~] DEB  - Signature not implemented
[~] AR   - Signature not implemented

Fixed (2025-12-25):
[x] RPM  - Added signature (0xEDABEEDB)
[x] AVI  - Fixed RIFF subtype detection
[x] WAV  - Fixed RIFF subtype detection

Known issues:
[!] JavaClass - Detected as Mach-O (0xCAFEBABE collision, unfixable)

Not tested (no signature defined):
[ ] AVIF, HEIC, MKV, TAR, DMG, ISO, DOCX/XLSX/PPTX, ODF
```

### Fuzzing Improvements

```
[ ] Add --target option to run_fuzz.py for external testing
[ ] Implement adaptive rate limiting in production fuzzer
[ ] Add hypothesis property-based tests for MIME detection
[ ] Create polyglot generator for automated MIME confusion testing
[x] Add timing attack tests for authentication endpoints
```

### Penetration Testing (from PENTEST_PLAN.md)

```
[x] Race condition: Burn-after-read via HEAD then GET (SAFE)
[ ] Race condition: Content hash deduplication counter
[ ] DoS: Memory exhaustion via unique IP rate limits
[ ] DoS: Anti-flood list growth under load
[ ] CLI: Clipboard command injection validation
[ ] CLI: Certificate file permission exposure
```

### Documentation

```
[ ] Add remaining MIME test results to security assessment
[ ] Document rate limiting behavior under attack
[ ] Create threat model diagram
[ ] Add security headers audit to CI pipeline
```

---

## Test Commands

```bash
# Local fuzzer (starts isolated server)
./venv/bin/python tests/fuzz/run_fuzz.py --verbose

# Quick smoke test
./venv/bin/python tests/fuzz/run_fuzz.py --quick

# Specific phases only
./venv/bin/python tests/fuzz/run_fuzz.py --phases 1,2,3

# Hypothesis tests (via pytest)
./venv/bin/pytest tests/test_fuzz.py -v

# Production fuzzer (rate limited)
python /tmp/prod_fuzz.py
```

---

## Security Controls Verified

| Control | Implementation | Verified |
|---------|----------------|----------|
| X-Content-Type-Options | nosniff | Yes |
| Content-Security-Policy | default-src 'none' | Yes |
| X-Frame-Options | DENY | Yes |
| Magic byte detection | First 16 bytes, 45 signatures | Yes |
| Input sanitization | Werkzeug header handling | Yes |
| SQL injection prevention | SQLAlchemy parameterized queries | Yes |
| SSTI prevention | No user content in templates | Yes |
| Path traversal prevention | ID validation regex | Yes |
| Constant-time password check | PBKDF2 600k iterations | Yes |
| Burn-after-read race condition | HEAD triggers deletion | Yes |
| RIFF container detection | Subtype check (WEBP/AVI/WAVE) | Yes |

---

## Notes

- Production testing requires rate limit awareness (1.5s+ delay)
- X-SSL-Client-SHA1 spoofing requires TRUSTED_PROXY_SECRET in production
- /metrics endpoint intentionally exposed for Prometheus
- Hypothesis tests use Flask test client (in-memory, not network)