---
created: "2026-03-08"
type: resource
tags:
  - resource
  - homelab
  - security
  - proxmox
  - networking
  - vulnerability-scanning
---

# PVE Security Scanner

## Goal

在 Proxmox VE 上搭建一台专用的内网安全扫描 VM，用于定期进行网络安全评估、漏洞扫描和合规检查。

## Architecture

```
+------------------+
|   PVE Host       |
|  +--------------+|     PVE Firewall (Layer 1)
|  | Scanner VM   ||     - IN: only admin IPs -> SSH/9392
|  | Ubuntu 24.04 ||     - OUT: internal nets + update_targets IPSET
|  | 4C / 8G / 80G||
|  +--------------+|
|        |         |
+--------|--------+
         | vmbr0 (bridge)
         |
   ======|==================== Internal Network (192.168.68.0/24)
   |     |     |     |
  [Host] [Host] [Host] [Switch/Router]
```

## VM Specs

| Resource | Value |
|----------|-------|
| Hostname | network-scanner |
| IP | 192.168.68.84 |
| OS | Ubuntu 24.04 (cloud-init) |
| Kernel | 6.8.0-101-generic |
| CPU | 4 cores (host type) |
| RAM | 8 GB |
| Disk | 80 GB |
| Network | vmbr0 bridge, 192.168.68.0/24 |
| SSH User | kai (1Password managed key) |
| Admin User | scanner-admin |

## Security Architecture (Defense in Depth)

### Layer 1: PVE Firewall (Hypervisor)

在 Proxmox 层面限制 VM 网络访问，即使 VM 被攻陷也无法绕过。

| Direction | Rule | Purpose |
|-----------|------|---------|
| IN | Admin IPs -> TCP 22 | SSH 管理 |
| IN | Admin IPs -> TCP 443, 9392 | OpenVAS Web UI |
| IN | Internal nets -> ICMP | Ping |
| OUT | -> Internal nets (all) | 扫描内网 |
| OUT | -> update_targets IPSET TCP 80/443 | 漏洞库更新、包管理 |
| OUT | -> UDP 53/123 | DNS / NTP |
| Default | DROP | 其他全部拒绝 |

Config: `/etc/pve/firewall/200.fw`

Admin IPs 默认 `192.168.68.0/24`（整个内网段），可通过 `SCANNER_ADMIN_IPS` 环境变量覆盖。

### Layer 2: nftables (VM Internal)

VM 内部使用 nftables 做第二层防护，包含动态封禁功能。

**Key features:**
- `blocked_ips` set: 动态 IP 封禁（带超时自动解封）
- `ssh_bruteforce` set: SSH 暴力破解自动检测（3次/分钟触发，15分钟封禁）
- Output policy DROP: 出站默认拒绝，仅白名单放行
- 所有 DROP 事件记录日志
- Docker 接口使用 `iifname "docker*"` / `iifname "br-*"` 通配（不要求接口预先存在）

**管理命令:**

```bash
# 查看规则
nft list ruleset

# 手动封禁 IP（1小时）
nft add element inet firewall blocked_ips { 1.2.3.4 timeout 1h }

# 查看被封禁的 IP
nft list set inet firewall blocked_ips

# 重载规则
systemctl restart nftables
```

Config: `/etc/nftables.conf`

### Layer 3: SSH Hardening

| Setting | Value |
|---------|-------|
| Authentication | Public key only (1Password) |
| Root login | Disabled |
| Max auth tries | 10 |
| Ciphers | chacha20-poly1305, aes256-gcm |
| KEX | sntrup761x25519, curve25519 |
| Fail2ban | 3 failures -> 1h ban (nftables backend) |
| AllowUsers | `scanner-admin kai` |
| Forwarding | DisableForwarding yes |
| Banner | /etc/issue.net |

Config: `/etc/ssh/sshd_config.d/99-scanner-hardening.conf`

### Layer 4: System Hardening

**Kernel (sysctl):**
- IP forwarding disabled
- ICMP redirects ignored
- SYN flood protection (syncookies)
- Reverse path filtering (anti-spoofing)
- Martian packet logging
- ASLR enabled, ptrace restricted

**Auditing:**
- `auditd`: 监控 /etc, auth, sudo, network, cron, scanner config 变更
- `AIDE`: 文件完整性检查 (daily 3am)
- `Lynis`: 安全审计 (weekly Sunday 2am)
- Core dumps disabled

Config: `/etc/sysctl.d/99-security-scanner.conf`, `/etc/audit/rules.d/scanner-audit.rules`

## Installed Tools

| Tool | Purpose | Usage |
|------|---------|-------|
| **OpenVAS/Greenbone** | 全面漏洞管理平台 | Web UI `https://192.168.68.84` (nginx -> gsad) |
| **Nmap** | 网络发现、端口扫描 | `nmap -sV --script=safe <target>` |
| **Nuclei** | 快速漏洞扫描 (模板驱动, SHA256 校验) | `nuclei -u <url>` |
| **httpx** | HTTP 探测、服务识别 (SHA256 校验) | `httpx -l hosts.txt` |
| **Nikto** | Web 服务器扫描 | `nikto -h <url>` |
| **testssl.sh** | TLS/SSL 安全检测 | `testssl <host:port>` |
| **NetExec** | SMB/RDP/WinRM 评估 | `netexec smb <target>` |

## Scanning Workflow

### Quick Scan (Automated)

```bash
/opt/scans/scripts/quick-scan.sh 192.168.68.0/24
```

Steps:
1. Host discovery (`nmap -sn`)
2. Port scan top 1000 (`nmap -sV --script=safe`)
3. HTTP service detection (`httpx`)
4. Vulnerability scan (`nuclei` medium/high/critical)

Results saved to `/opt/scans/results/<timestamp>/`

### Full Scan (OpenVAS)

1. Start containers: `cd /opt/greenbone && docker compose up -d`
2. Wait for feed sync (first time: 30-60 min)
3. Access Web UI: `https://192.168.68.84` (self-signed cert, accept warning)
4. Create Target -> Create Task -> Run Scan
5. Export report (PDF/CSV)

### Targeted Scans

```bash
# TLS/SSL audit
testssl 192.168.68.10:443

# Web server scan
nikto -h https://192.168.68.10

# SMB assessment
netexec smb 192.168.68.0/24

# Full port scan single host
nmap -sV --script=safe -p- -T4 192.168.68.10
```

## Monitoring

| Check | Schedule | Tool |
|-------|----------|------|
| Disk usage | Every 6h | `/opt/scans/scripts/check-disk.sh` |
| OpenVAS health | Every 30min | `/opt/scans/scripts/check-openvas.sh` |
| File integrity | Daily 3am | AIDE |
| Security audit | Weekly Sun 2am | Lynis |
| Old results cleanup | Weekly Sun 4am | find (maxdepth 1, >90 days, logged) |
| Nuclei templates | Weekly Mon 5am | `nuclei -update-templates` |
| Daily summary | Daily | Logwatch |

Logs: `/var/log/scanner/`

## Deployment

### Method: Cloud-Init Template Clone

1. PVE Web UI -> 选中 Cloud-Init 模板 -> 右键 Clone (Full Clone)
2. Cloud-Init 标签设置: user `kai`, SSH key (1Password), IP `192.168.68.84/24`
3. Hardware: 4C / 8G / 80G disk

### Copy Scripts to VM

```bash
scp -r C:/Users/yaoji/git/pve-security-scanner/vm kai@192.168.68.84:/tmp/scanner-setup
```

### Execute (in order)

```bash
# 设置环境变量
export SCANNER_ADMIN_IPS='192.168.68.0/24'
export SCANNER_DNS_SERVERS='192.168.68.1'

# 一键执行（或逐个执行）
sudo -E bash /tmp/scanner-setup/setup.sh

# 或逐个:
sudo -E bash /tmp/scanner-setup/01-system-harden.sh
sudo -E bash /tmp/scanner-setup/02-firewall.sh
sudo -E bash /tmp/scanner-setup/04-install-tools.sh   # Docker 先装
sudo usermod -aG docker scanner-admin                  # 补加 docker 组
sudo -E bash /tmp/scanner-setup/03-ssh-harden.sh       # 再跑 SSH
sudo -E bash /tmp/scanner-setup/05-monitoring.sh
sudo -E bash /tmp/scanner-setup/06-docker-autostart.sh

# OpenVAS 密码
cd /opt/greenbone && docker compose up -d
docker compose exec -u gvmd gvmd gvmd --user=admin --new-password=<PASSWORD>

# 重启
sudo shutdown -r now
```

### Post-Deployment Checklist

- [x] VM created from cloud-init template
- [x] SSH key configured (1Password, ed25519)
- [x] System hardening (01) applied
- [x] nftables firewall (02) applied - ADMIN_IPS = 192.168.68.0/24
- [x] Docker installed (Ubuntu source fix applied)
- [x] SSH hardening (03) applied - AllowUsers scanner-admin kai, MaxAuthTries 10
- [x] Security tools (04) installed
- [x] Monitoring (05) configured
- [x] Docker autostart (06) enabled - systemd greenbone-openvas.service
- [x] OpenVAS Web UI accessible - `https://192.168.68.84` (nginx port 443+9392)
- [ ] Feed sync complete (in progress, ~30-60 min)
- [ ] First quick scan completed
- [ ] `lynis audit system` score verified

## Deployment Notes

### Issues Encountered

1. **Docker source wrong distro**: 脚本原写 Debian 源，实际系统是 Ubuntu 24.04 (noble)。已修复为自动检测 `${ID}` (debian/ubuntu)
2. **nftables rate limit 不能用 define**: `define SSH_RATE_LIMIT = 5/minute` 语法错误，nftables 不支持 define 变量做 rate limit，改为内联值
3. **`iif "docker0"` 要求接口已存在**: Docker 未安装时 docker0 不存在导致报错，改为 `iifname "docker*"` 通配
4. **03-ssh-harden.sh docker 组不存在**: 需先运行 04 安装 Docker，再运行 03 创建用户
5. **SSH `sshd.service` not found**: Ubuntu 用 `ssh.service`，已修复为 `ssh 2>/dev/null || sshd`
6. **AllowUsers 只有 scanner-admin**: cloud-init 用户 `kai` 被拒绝登录，已加入 AllowUsers
7. **MaxAuthTries 3 太小**: 1Password 管理多个 key 逐个尝试会超限，改为 10
8. **ADMIN_IPS 设成 VM 自身 IP**: 导致工作站无法 SSH，改为整网段 `192.168.68.0/24`
9. **Greenbone 镜像名变更**: `greenbone/xxx` 已迁移到 `registry.community.greenbone.net/community/xxx`，架构改为 nginx + gsad + gsa 分离
10. **nginx 9392 端口重定向到 443**: 需同时暴露 443 端口，docker-compose 已加 `0.0.0.0:443:443`

### Recommended Execution Order (revised)

01 -> 02 -> 04 (Docker) -> 03 (SSH, needs docker group) -> 05 -> 06

## Scripts Location

Repo: https://git.colacoder.com/kai/pve-security-scanner

```
pve-security-scanner/
├── pve/
│   ├── create-vm.sh          # VM creation (idempotent)
│   └── firewall.sh           # PVE-level firewall (env var guard)
├── vm/
│   ├── setup.sh              # One-click ordered execution
│   ├── 01-system-harden.sh   # OS hardening
│   ├── 02-firewall.sh        # nftables rules
│   ├── 03-ssh-harden.sh      # SSH + fail2ban
│   ├── 04-install-tools.sh   # Security tools (auto-detect distro)
│   ├── 05-monitoring.sh      # Logging + cron
│   └── 06-docker-autostart.sh # OpenVAS systemd service
└── README.md
```

## Related

- [[Proxmox VE]]
- [[Home Network]]
- [[Security Best Practices]]
