A discussion - Claude - Vert

This ladies and gentleman, is the best thing about running your own public servers, you learn a great deal, and although I have had numerous problems, including a lack of time lately, I highly recommend this, as long as you have backups, as you will need them.

Vert is particularly attractive to attackers because:

• It handles video file conversions - complex parsers with historical vulnerabilities
• Video file conversion is not enabled on my server - I throw the ball.
• Video codecs (FFmpeg/libav underneath) have had numerous CVEs
• Large file uploads = more attack surface
• Processing-intensive = good DoS target

Here's how to implement ClamAV scanning for Vert:

1. Where to install:

• Inside your Podman LXC container where Vert runs
• NOT on the Proxmox host

2. The scanning pipeline for Vert specifically:

User upload via Cloudflare → Zaroxy → Vert receives file → 
ClamAV scans BEFORE conversion → If clean: convert → Serve result
                                → If malicious: delete + log + reject

3. Implementation approach:

Option A - On-access scanning (recommended):

• Install clamav-daemon and clamav-freshclam in the LXC
• Configure clamonacc to watch Vert's upload directory
• Malicious files get quarantined automatically before conversion starts

Option B - Pre-processing scan:

• Modify Vert's upload handling to run clamdscan on each file
• Only proceed with conversion if scan returns clean
• Requires code modification or wrapper script

4. Specific to your Podman setup:

• Install ClamAV packages inside the LXC (not as a Podman container)
• Mount Vert's upload volume where ClamAV can access it
• Ensure proper permissions between ClamAV daemon and Vert's process

5. Additional Vert-specific hardening:

• Set strict file size limits (video files can be huge)
• Timeout conversions (prevent resource exhaustion)
• Validate video file headers before passing to FFmpeg
• Run FFmpeg with restricted permissions

Another question and answer

Perfect - that's actually the cleanest setup for this. Here's how to implement ClamAV scanning:

Architecture:

Podman LXC Container
├── ClamAV (installed in LXC, not containerized)
├── Podman: Vert container
│   └── Upload volume (mounted from LXC filesystem)
└── ClamAV watches the upload volume on the LXC filesystem

Implementation steps:

1. Install ClamAV in the LXC (not in Podman):

# Inside your Podman LXC
apt update
apt install clamav clamav-daemon clamav-freshclam

2. Identify Vert's upload volume:

podman volume inspect <vert-volume-name>
# Look for "Mountpoint" - this is where files actually land on the LXC filesystem

3. Configure ClamAV to scan that mountpoint:

• Use clamonacc for real-time scanning of the volume directory
• Or use a script that scans files before Vert processes them

4. The key advantage of your setup:

• ClamAV runs in the LXC with low overhead
• It can scan the Podman volume before Vert container processes files
• Vert container remains isolated and minimal
• If ClamAV has issues, it doesn't affect Vert directly

5. Podman volume permissions: You'll need to ensure ClamAV daemon can read the Podman volume mountpoint (usually /var/lib/containers/storage/volumes/...)

The critical question: Does Vert have a specific upload directory/volume that you've defined in your Podman run/compose configuration? If so, what's it called? That's what we need ClamAV to monitor.

Also - is Vert processing files immediately on upload, or queuing them? This affects whether we use real-time scanning vs pre-processing scanning.

Good assumption - yes, Vert processes uploads immediately on landing based on typical web-based conversion tool patterns.

This means you need real-time/on-access scanning to catch files before Vert's conversion process touches them.

Here's your implementation strategy:

1. Find Vert's volume configuration:

# Inside your Podman LXC
podman ps | grep vert
podman inspect <vert-container-name> | grep -A 10 "Mounts"

Look for the upload/temp directory volume - it's likely something like:

• /uploads
• /tmp
• /app/uploads

2. Set up ClamAV with on-access scanning:

# In the LXC (not in container)
apt install clamav clamav-daemon clamav-freshclam clamonacc

# Update virus definitions
systemctl stop clamav-freshclam
freshclam
systemctl start clamav-freshclam
systemctl start clamav-daemon

3. Configure clamonacc to watch the Podman volume:

# Find the actual filesystem path
podman volume inspect <volume-name>
# Note the "Mountpoint" path

# Start on-access scanning (example)
clamonacc -F --fdpass --move=/var/quarantine /var/lib/containers/storage/volumes/<volume-name>/_data

The challenge: On-access scanning works best when files are written to disk. Since Vert processes immediately, you might have a race condition.

Alternative approach - Application-level scanning: Create a wrapper/sidecar that:

1. Intercepts uploads before they reach Vert
2. Scans with clamdscan
3. Only passes clean files to Vert

Quick question: Can you share the Vert GitHub repo URL or your podman-compose.yml? That would let me give you exact configuration rather than generalized guidance.

URL link shared with Claude

Perfect! Looking at the compose file, here's what's happening:

Vert's volume structure:

volumes:
  - ./data:/app/data

So uploads land in ./data on your LXC filesystem, mapped to /app/data inside the container.

Your ClamAV implementation:

1. Install ClamAV in the Podman LXC:

apt update
apt install clamav clamav-daemon clamav-freshclam
systemctl stop clamav-freshclam
freshclam
systemctl start clamav-freshclam clamav-daemon

2. Locate Vert's data directory:

# Find where you deployed Vert's compose file
cd /path/to/vert/
ls -la data/

This ./data directory is where uploads land before processing.

3. Set up on-access scanning:

# Create quarantine directory
mkdir -p /var/quarantine

# Configure clamonacc to watch Vert's data directory
clamonacc -F --fdpass --move=/var/quarantine /path/to/vert/data

The problem with Vert specifically: Looking at the code structure, Vert uses in-memory processing for many conversions - files may not hit disk long enough for traditional on-access scanning.

Better approach for Vert - Scheduled scanning:

# Cron job to scan uploads directory every minute
* * * * * clamdscan --move=/var/quarantine /path/to/vert/data --quiet

Or use inotify-based scanning:

apt install inotify-tools

# Script that scans on file creation
inotifywait -m /path/to/vert/data -e create -e moved_to |
    while read path action file; do
        clamdscan --move=/var/quarantine "$path$file"
    done

Most practical solution: Add a reverse proxy layer in front of Vert that scans uploads before passing them through. Would you like me to create a scanning proxy container config for this?

Another question and answer

I need to clarify something important here: Zoraxy cannot scan file contents for malware - it operates at the HTTP/reverse proxy layer, not the file content layer.

What Zoraxy does:

• HTTP request filtering
• Rate limiting
• WAF rules
• Header manipulation
• Request size limits

What Zoraxy cannot do:

• Scan uploaded file contents for viruses
• Inspect inside ZIP files, videos, PDFs
• Detect malicious payloads in valid file formats

Your architecture needs an additional layer:

Internet → Cloudflare Tunnel → Zoraxy → **Scanning Proxy** → Vert

Option 1: Lightweight scanning sidecar container

Create a simple scanning proxy as another Podman container in your LXC:

# Add to your compose or create separate compose file
services:
  vert-scanner:
    image: mkodockx/docker-clamav:alpine
    container_name: vert-scanner
    volumes:
      - ./data:/scan:rw
    restart: unless-stopped
    
  vert-upload-proxy:
    image: nginx:alpine
    container_name: vert-upload-proxy
    volumes:
      - ./nginx-scan.conf:/etc/nginx/nginx.conf:ro
      - ./data:/app/data:rw
    ports:
      - "8081:80"  # Expose this to Zoraxy instead of Vert directly
    depends_on:
      - vert-scanner
      - vert

nginx-scan.conf that intercepts uploads:

events {}
http {
    upstream vert {
        server vert:3000;
    }
    
    server {
        listen 80;
        client_max_body_size 500M;
        
        location / {
            # Pass non-upload requests directly
            proxy_pass http://vert;
        }
        
        location /upload {
            # Save upload to temp location
            client_body_temp_path /app/data/temp;
            
            # Scan would happen here via script
            # Then proxy to Vert if clean
            
            proxy_pass http://vert;
        }
    }
}

Option 2: Simpler approach - Post-processing cleanup

Since Vert processes files immediately, focus on damage control:

1. Zoraxy - limits request size, rate limits (already configured ✓)
2. Scheduled ClamAV scans - catch malicious files in data directory
3. Container isolation - keep Vert rootless and restricted
4. Monitoring - alert on suspicious activity

# Cron in LXC - scan Vert's data dir every 5 minutes
*/5 * * * * /usr/bin/clamdscan --infected --move=/var/quarantine /path/to/vert/data --quiet && logger "Vert scan complete"

My recommendation given your setup: Use Option 2 - it's simpler and acknowledges that real-time scanning of immediate-processing apps is complex. Focus on:

• Zoraxy rate limiting (done ✓)
• Regular ClamAV scans of the data directory
• Vert container running rootless
• Good logging and monitoring

Question: Are you seeing actual malicious traffic to Vert, or is this preventative hardening?

Hell of a question but since I throw the ball lets answer both

That changes everything - you're actively under attack. This needs immediate action.

Immediate steps:

1. Lock down Vert NOW via Zoraxy:

• Enable geographic restrictions (block countries you don't need) - done already
• Set aggressive rate limiting (e.g., 5 uploads per IP per hour) - done now
• Enable authentication if Zoraxy supports it for specific routes - hmmm?
• Consider IP whitelisting if this is primarily for your own testing - done already

2. Implement ClamAV scanning immediately:

# In your Podman LXC
apt install clamav clamav-daemon inotify-tools

# Update definitions
freshclam
systemctl start clamav-daemon

# Create quarantine and logging
mkdir -p /var/quarantine
touch /var/log/vert-scan.log

3. Real-time scanning script for Vert's data directory:

#!/bin/bash
# /usr/local/bin/vert-watcher.sh

WATCH_DIR="/path/to/vert/data"
QUARANTINE="/var/quarantine"
LOG="/var/log/vert-scan.log"

inotifywait -m -r -e create,moved_to --format '%w%f' "$WATCH_DIR" | while read FILE
do
    echo "$(date): Scanning $FILE" >> "$LOG"
    
    # Scan the file
    RESULT=$(clamdscan --no-summary "$FILE" 2>&1)
    
    if echo "$RESULT" | grep -q "FOUND"; then
        echo "$(date): THREAT DETECTED - $FILE" >> "$LOG"
        # Move to quarantine
        mv "$FILE" "$QUARANTINE/" 2>/dev/null
        # Log the IP if possible (check Vert logs)
        logger -t VERT-SECURITY "Malicious file quarantined: $FILE"
    fi
done

chmod +x /usr/local/bin/vert-watcher.sh

# Create systemd service
cat > /etc/systemd/system/vert-watcher.service <<EOF
[Unit]
Description=Vert Upload Scanner
After=clamav-daemon.service

[Service]
ExecStart=/usr/local/bin/vert-watcher.sh
Restart=always
User=root

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable --now vert-watcher

4. Analyze what you're seeing:

# Check Vert's logs
podman logs vert -f

# Check quarantine
ls -lah /var/quarantine/

# What types of attacks?
tail -f /var/log/vert-scan.log

5. Consider temporary measures:

• Take Vert offline temporarily if attacks are severe
• Move it behind Cloudflare Access (requires login)
• Implement CAPTCHA via Zoraxy if supported
• Whitelist only your IP for testing

Critical questions:

1. What are you seeing in the attacks? (malicious files, exploitation attempts, DoS?)
2. Do you need Vert publicly accessible, or can you restrict it?
3. What does Zoraxy's logs show about the attack patterns?

This isn't just hardening - you need active defense right now.

So much to learn and I mean SO MUCH to learn.

Added to the project list and with the forensics already built in Zoraxy I need to introduce Claude to it and see if my new silicon friend can help me fine tune the script, the fail2ban, turn on AbuseIPDB and move on from there.

This is the problem with all of this and cybersecurity, add a new service and watch it snowball into new problems and a staggering amount of WTH and WTF.

Love this stuff.

#enoughsaid