Listen to this Post
Introduction:
Modern Linux servers face relentless authentication attacks—brute-force and password spraying attempts targeting custom login pages, APIs, and admin panels. Traditional tools like fail2ban work but often become resource-heavy “gas factories.” SysWarden v2.00 emerges as a lightweight, transparent, “no-bullshit” firewall orchestrator that combines a clean CLI with an innovative Generic Web Auth Guard module to automatically detect and block these attacks, regardless of the endpoint or framework.
Learning Objectives:
- Deploy and configure SysWarden v2.00 on a Linux server to replace or augment existing brute-force protection.
- Implement the new Generic Web Auth Guard (Jail 47) to block password spraying and brute-force attempts on custom HTML/PHP login forms.
- Audit and customize SysWarden’s open-source firewall orchestration rules using Linux iptables/nftables and CLI commands.
You Should Know:
- Deploying SysWarden v2.00: From GitHub to Active Firewall Orchestration
SysWarden is a Linux-native firewall orchestrator designed for minimal resource consumption. It works by monitoring system logs, application logs, or custom authentication endpoints, then dynamically updating firewall rules to block offending IPs.
Step‑by‑step installation and basic setup:
Clone the official repository git clone https://github.com/duggytuxy/syswarden cd syswarden Review the installation script (always audit open-source code) cat install.sh Run installation as root (SysWarden requires firewall manipulation) sudo bash install.sh Verify installation and version syswarden --version Expected output: SysWarden v2.00 Check the new geometric CLI interface syswarden status
Configuration essentials:
SysWarden uses jail configuration files (similar to fail2ban but leaner). The main configuration directory is /etc/syswarden/. The new Jail 47 (Generic Web Auth Guard) is defined in /etc/syswarden/jail.d/web-auth.conf.
Example custom jail for a PHP login page at /login.php sudo nano /etc/syswarden/jail.d/custom-login.conf
Add the following configuration:
[login-guard] enabled = true filter = web-auth-generic logpath = /var/log/nginx/access.log maxretry = 5 findtime = 300 bantime = 3600 action = iptables-multiport[name=login, port="http,https", protocol=tcp] Custom regex for your login endpoint failregex = ^<HOST> . "POST /login.php. 401
After saving, restart SysWarden:
sudo systemctl restart syswarden sudo syswarden status jail login-guard
Windows alternative (for cross-platform defenders):
While SysWarden is Linux-native, you can simulate similar behavior on Windows using PowerShell + Windows Defender Firewall:
Monitor IIS logs for 401 statuses on login.aspx
$logPath = "C:\inetpub\logs\LogFiles\W3SVC1.log"
$failedAttempts = Get-Content $logPath | Select-String " 401 " | Select-String "POST /login.aspx"
$offenders = $failedAttempts | ForEach-Object { ($_ -split ' ')[bash] } | Group-Object
$offenders | Where-Object Count -gt 5 | ForEach-Object {
New-NetFirewallRule -DisplayName "Blocked Brute $($<em>.Name)" -Direction Inbound -RemoteAddress $</em>.Name -Action Block
}
- Generic Web Auth Guard (Jail 47): Blocking Password Spraying Across Any Framework
Password spraying attacks try a few common passwords across many usernames, evading traditional per-user brute-force detection. SysWarden’s Jail 47 analyzes login endpoint response codes (401, 403, 302 to error pages) regardless of the backend—HTML, PHP, Node.js, or Python frameworks.
How it works:
The guard parses web server logs (nginx, Apache, or custom) using configurable regex patterns. It tracks failed authentication attempts by source IP, ignoring username variations. Once a threshold is exceeded, it injects an iptables/nftables rule to drop all traffic from that IP.
Step‑by‑step enablement and tuning:
Enable the Generic Web Auth Guard jail sudo syswarden jail enable jail47 Jail 47 is named "web-auth-generic" in configuration Edit the filter definition to match your exact login endpoint sudo nano /etc/syswarden/filter.d/web-auth-generic.conf
Example filter for a JSON-based API login:
[bash] failregex = ^<HOST> - - [.] "POST /api/v1/login HTTP/1.[bash]" 401 ignoreregex =
For a WordPress wp-login.php:
failregex = ^<HOST> . "POST /wp-login.php. HTTP/\d.\d" 200 (?!.already logged in)
Test your regex before deploying:
sudo syswarden test-regex /var/log/nginx/access.log /etc/syswarden/filter.d/web-auth-generic.conf
Monitoring active blocks:
List currently banned IPs sudo syswarden ban list Show firewall rules added by SysWarden (iptables backend) sudo iptables -L INPUT -n | grep syswarden For nftables backend sudo nft list chain inet syswarden input
To temporarily unban an IP:
sudo syswarden unban 192.168.1.100
- Auditing and Hardening Your Firewall Orchestration with Linux Commands
SysWarden’s open architecture allows you to inspect every rule it creates. Understanding the underlying commands is crucial for security professionals.
Inspecting SysWarden’s iptables ruleset:
View all chains created by SysWarden sudo iptables -L -v -n | grep -E "Chain.syswarden|syswarden" Dump the entire ruleset for auditing sudo iptables-save | grep syswarden > syswarden_rules_backup.txt
Manual rule addition (bypassing SysWarden for testing):
Block an IP immediately without waiting for SysWarden sudo iptables -A INPUT -s 203.0.113.45 -j DROP Rate-limit SSH connections (complementary to SysWarden) sudo iptables -A INPUT -p tcp --dport 22 -m conntrack --ctstate NEW -m recent --set sudo iptables -A INPUT -p tcp --dport 22 -m conntrack --ctstate NEW -m recent --update --seconds 60 --hitcount 4 -j DROP
For Windows Server with similar orchestration (using PowerShell and netsh):
Block an IP manually netsh advfirewall firewall add rule name="ManualBlock" dir=in action=block remoteip=203.0.113.45 Show current blocking rules netsh advfirewall firewall show rule name=all | findstr "Block"
Testing your SysWarden configuration with simulated attacks:
Simulate failed logins using curl (replace with your login endpoint)
for i in {1..10}; do curl -X POST -d "user=admin&pass=wrong$i" http://localhost/login.php -I; sleep 1; done
Check if SysWarden blocked your own IP (be careful not to lock yourself out)
sudo syswarden ban list | grep $(curl -s ifconfig.me)
If you block yourself, console access is required. Always whitelist management IPs:
sudo syswarden whitelist add $(your_management_ip)
4. Optimizing SysWarden for Low-Resource Production Environments
SysWarden’s “no-bullshit” promise means it avoids heavy databases or complex dependencies. The core orchestrator runs as a lightweight daemon that tail log files and invokes iptables/nftables directly.
Resource tuning:
Check current memory and CPU usage ps aux | grep syswarden Typically under 20MB RAM Adjust polling intervals for high-traffic servers sudo nano /etc/syswarden/syswarden.conf
Modify these parameters:
[bash] poll_interval = 5 Seconds between log scans (default 10) max_retry_attempts = 3 Number of failures before banning ban_time_default = 3600 Ban duration in seconds find_time_window = 600 Time window for counting retries
Integration with cloud firewalls (AWS Security Groups, Azure NSG):
SysWarden cannot directly modify cloud-managed firewalls, but you can create a script that syncs banned IPs to cloud APIs:
Example: Export banned IPs to AWS WAF sudo syswarden ban list --raw > /tmp/banned_ips.txt aws wafv2 update-ip-set --name MyBlocklist --addresses file:///tmp/banned_ips.txt
Schedule this via cron:
crontab -e Add: /5 /usr/local/bin/sync-syswarden-to-aws.sh
5. Extending SysWarden with Custom Actions and Notifications
When SysWarden bans an IP, you can trigger alerts to Slack, Discord, or SIEM.
Create a custom action script:
sudo nano /etc/syswarden/action.d/slack-notify.sh
!/bin/bash
IP=$1
BANTIME=$2
JAIL=$3
WEBHOOK_URL="https://hooks.slack.com/services/YOUR/WEBHOOK"
curl -X POST -H 'Content-type: application/json' \
--data "{\"text\":\"🚨 SysWarden banned $IP for $BANTIME seconds (jail: $JAIL)\"}" \
$WEBHOOK_URL
Make it executable and reference in jail config:
sudo chmod +x /etc/syswarden/action.d/slack-notify.sh
In your jail configuration, add:
action = iptables-multiport[name=login, port="http,https"] slack-notify
Testing notifications:
sudo syswarden ban add 192.0.2.1 --jail test --action slack-notify
What Undercode Say:
- Open-source firewall orchestration doesn’t have to be bloated – SysWarden v2.00 proves that effective brute-force protection can run on minimal resources while remaining fully auditable.
- Password spraying is often overlooked – The Generic Web Auth Guard addresses a critical gap in traditional tools by focusing on endpoint response patterns rather than per-user failures.
- Community-driven security wins – The project’s transparent development and quick iteration (v2.00 with multiple real-world tests) exemplify how open-source can outpace proprietary solutions.
Prediction:
As API-driven applications and custom login pages proliferate, traditional fail2ban configurations will become obsolete. Expect SysWarden-like “generic auth guards” to become standard in cloud-native security stacks within 18 months, with integrations into Kubernetes admission controllers and serverless firewalls. The shift from per-username to per-endpoint anomaly detection will redefine how we defend against credential-based attacks.
▶️ Related Video (82% Match):
🎯Let’s Practice For Free:
IT/Security Reporter URL:
Reported By: Laurent Minne – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅
