7 Free Firewall Options for Node.js Apps in 2026
Free firewalls for Node.js — application-layer, edge-layer, and self-hostable. Honest tradeoffs for each.
7 Free Firewall Options for Node.js Apps in 2026
Free firewalls genuinely exist. The catches are non-obvious. Here are the seven options worth considering, ranked by total effort + cost (lower = better).
For broader context see the SecureNow Firewall page.
1. SecureNow Firewall (recommended)
What it is. Application-layer Node.js firewall via npm preload. 500k known-bad IPs, hourly refresh, automatic Googlebot/GPTBot/ClaudeBot allowlist.
Setup. npm install securenow + node -r securenow/firewall-only app.js. 5 minutes.
Free tier. Free at every traffic level for the firewall layer. Free 1 GB/month for the broader observability tier.
Catches. ~30% of malicious traffic at the IP-reputation layer. Adds bot-UA filtering for free.
Misses. Layer-3/4 attacks (DDoS), sophisticated bots that mimic browsers perfectly.
Verdict. Best ROI for most Node apps. See the page.
2. Cloudflare Free Tier
What it is. CDN + WAF + DDoS protection. Free tier includes basic WAF, basic bot protection, unlimited bandwidth (with TOS limits).
Setup. Change DNS to Cloudflare. Configure rules in dashboard.
Free tier. Generous; covers most personal projects.
Catches. Layer-3/4 attacks, common attack signatures, basic bot heuristics.
Misses. Sophisticated bots from residential proxies; the free Bot Management is heuristic-only.
Verdict. Best free firewall if you're willing to put your DNS through Cloudflare. The DNS lock-in is real.
3. AWS WAF (cost-only, technically free for limited usage)
What it is. AWS-native WAF with managed rule sets. Not strictly free — billed per request — but very cheap at small scale.
Setup. Provision in AWS console, attach to ALB or CloudFront distribution.
Cost. ~$5 + ~$0.60 per 1M requests. Effectively free for small apps.
Catches. OWASP Core Rule Set patterns, common attack signatures, bot-detection on AWS-curated rules.
Misses. Application-specific business-logic abuse.
Verdict. Good if you're already on AWS. The setup is more involved than NPM-package alternatives.
4. Hand-rolled Express middleware
What it is. Code your own filter using a public threat-intel feed.
Setup. Write middleware (~50 lines), pull blocklist nightly via cron, refresh.
Cost. Free in dollars; ~4 hours of engineering, ~30 minutes/month maintenance.
Catches. Whatever's in the feed you're using. AbuseIPDB free tier gives 10K IPs/day.
Misses. Real-time threats (your refresh is daily), allowlist maintenance for legitimate crawlers.
Verdict. Tinker-grade. Use this if you have specific custom requirements; otherwise option 1 is less work.
5. ModSecurity (self-hosted)
What it is. Open-source WAF with the OWASP Core Rule Set. Sits in front of your Node app via Nginx.
Setup. Install Nginx, install ModSecurity module, install OWASP CRS. Tune rules to reduce false positives. Multi-day project.
Cost. Free (self-hosted infrastructure).
Catches. OWASP Top 10 patterns, SQL injection, XSS — the same things commercial WAFs catch.
Misses. Bot management, rate limiting (need a separate Nginx module for that).
Verdict. Powerful, complex, high-maintenance. Most Node teams will be better served by SecureNow or Cloudflare.
6. Fail2ban (server-level)
What it is. Linux daemon that watches log files and bans IPs that fail too many times. Classic Linux server protection.
Setup. Install on each server, write filter rules for your application logs.
Cost. Free.
Catches. Per-IP credential stuffing if your auth logs are formatted recognizably; SSH brute force.
Misses. Distributed attacks, application-layer bots, anything that doesn't show up in log files in a recognizable format.
Verdict. Belt-and-suspenders for SSH. Not a primary application firewall in 2026.
7. Hand-rolled IP allowlist (most restrictive)
What it is. Block everything except a specific set of IPs you trust.
Setup. Maintain a list of allowed IPs, reject all others.
Cost. Free.
Catches. Everything that isn't on the allowlist.
Misses. Every legitimate user not on the allowlist.
Verdict. Only viable for internal-only services or very tightly-scoped APIs. Don't use on a public app.
The honest comparison
| Option | Setup | Maintenance | Effective at scale |
|---|---|---|---|
| SecureNow Firewall | 5 min | 0 | Very |
| Cloudflare free | 30 min (+DNS) | low | Yes |
| AWS WAF | 1 hour | low | Yes |
| Hand-rolled middleware | 4 hours | medium | Modest |
| ModSecurity | 1 week | high | Yes (with effort) |
| Fail2ban | 30 min | low | No (specific use) |
| Manual allowlist | 5 min | high | Internal-only |
Quick-pick
- Public-facing Node app, want minimum effort: SecureNow Firewall.
- Already on Cloudflare or willing to switch DNS: Cloudflare free tier.
- Already in AWS: AWS WAF.
- Want to learn or have specific needs: hand-rolled or ModSecurity.
Related
Frequently Asked Questions
What's the best free firewall for Node.js?
Depends on what you mean by 'free'. SecureNow Firewall is free with no caps. Cloudflare's free tier is generous but adds DNS lock-in. Hand-rolled middleware is free in dollars but costs engineering time.
Are free firewalls actually production-ready?
Yes for most. The free tier of SecureNow Firewall protects 500k+ IPs and refreshes hourly — the same data as enterprise feeds. Cloudflare's free tier blocks the obvious bad-actor categories.
What about for high-traffic apps?
Free tiers are mostly fine until you exceed certain thresholds (Cloudflare WAF rules limited, free CDN bandwidth caps). At very high scale you'll need paid tiers somewhere.
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