How to Stop DDoS Attacks on Your FiveM Server (Complete Guide)

Why FiveM Servers Get Attacked

If you run a FiveM server, you've probably seen it happen: everything is fine, players are online, and then suddenly the server drops. Players can't reconnect. The host panel shows nothing wrong. Your CPU isn't spiking. But the server is completely unreachable.

That's a DDoS attack — and it's more common on FiveM than most server owners realize.

FiveM uses UDP for all game traffic. UDP is what makes multiplayer games feel responsive, but it has a fundamental weakness: anyone can send a UDP packet to any IP address, and the destination has no way to refuse it without processing it first. Attackers exploit this to flood your server's IP with junk traffic until your hosting provider's network can't cope — or until your server's connection is saturated — and you fall offline.

This guide explains how these attacks work, why common "solutions" don't actually fix the problem, and what does.

How FiveM DDoS Attacks Work

There are two main attack types you'll encounter:

Volumetric Floods

The attacker sends a massive volume of UDP packets to your server IP. Even with fast hardware, your server's upstream bandwidth gets saturated. At 1 Gbps of flood traffic, a server on a 500 Mbps line simply cannot keep up — packets get dropped, and players time out.

These attacks are often amplified: the attacker doesn't send 1 Gbps directly. They send small packets to misconfigured services (DNS resolvers, NTP servers, Memcached) that reply with much larger responses — all directed at your IP. A 100 Mbps attack becomes 1 Gbps through amplification alone.

Protocol-Layer Attacks

More targeted attacks exploit FiveM's connection handshake or try to find patterns in your server's response to craft packets that cause high CPU usage. These don't need volume — a few thousand specially crafted packets per second can spike your server to 100% CPU.

What Doesn't Work

Cloudflare (alone)

Cloudflare proxies HTTP/HTTPS traffic — web pages, resource downloads, your server's API. It cannot proxy UDP game traffic, which is what FiveM actually uses for player connections and gameplay. Enabling Cloudflare on your domain protects your website, not your game server.

Your Hosting Provider's Firewall

Standard firewalls (iptables, Windows Firewall, basic VPS firewalls) operate at the kernel level — packets are already inside your server's networking stack before the firewall sees them. During a large flood, the CPU overhead of processing millions of packets per second through the kernel stack causes performance issues even before any bandwidth limit is hit.

More importantly: most shared hosting providers will null-route your IP (cut off all traffic to your server) if you receive large DDoS traffic, to protect other customers on the same infrastructure. Your "protection" is actually just being disconnected.

VPNs and Port Obscurity

Changing ports or hiding your IP through a personal VPN doesn't help once an attacker knows your real server IP. FiveM server IPs are publicly listed in the server browser — obscurity isn't an option.

What Actually Stops DDoS Attacks on FiveM

The only reliable solution is a dedicated reverse proxy that sits between the internet and your server, with specialized filtering built specifically for game UDP traffic.

Here's what this architecture looks like:

Attacker ──────────────────────────────X  (dropped at proxy)
Player  ──► proxy.yourdomain.com:30120 ──► [filter] ──► your-origin-server:30120

Your server's real IP is never exposed. The proxy absorbs all incoming traffic. Only clean, verified player packets are forwarded to your origin server.

For this to work properly, the proxy needs:

1. XDP-Based Packet Filtering

XDP (eXpress Data Path) is a Linux kernel technology that processes packets at the network driver level — before they even enter the kernel's networking stack. This means millions of packets per second can be inspected and dropped with almost zero CPU cost.

Traditional iptables rules process packets after they've traversed the full kernel stack. XDP bypasses this entirely. For DDoS mitigation, this difference is critical: when you're receiving 5 million packets per second, kernel-level processing collapses. XDP handles it.

2. Player Whitelisting

A generic packet filter blocks obvious junk but can still let through "valid-looking" UDP traffic. A FiveM-aware proxy can go further: it knows which player IPs are supposed to be connecting, and it can drop everything else at the packet level. New connections go through a handshake validation before getting whitelisted.

3. IP Concealment

The proxy must expose its own IP, not yours. Your server's real IP should be locked down — only accepting traffic from the proxy's IP range. This way, even if someone discovers your proxy address, a direct attack on your origin IP from other sources goes nowhere.

4. Scrubbing Center Infrastructure

Good anti-DDoS proxies are deployed at network edges inside large hosting providers (OVH, Hetzner, etc.) that have hundreds of Gbps of upstream bandwidth and can absorb massive volumetric attacks before any filtering even needs to happen. A 20 Gbps flood to a proxy sitting on a 1 Tbps edge network barely registers.

The false-positive problem with generic scrubbing centers

Here's what most anti-DDoS marketing doesn't tell you: generic scrubbing centers regularly kick legitimate players, and for FiveM this is a serious problem.

Large scrubbing services (OVH VAC, Path.net, Akamai Prolexic) are built for web traffic and enterprise networks. Their detection models look at packet patterns and flag anything that deviates from expected behavior. FiveM's UDP traffic profile is unusual by design — players send bursts of small packets, connection patterns vary heavily by game mode, certain resources trigger brief bandwidth spikes, and FiveM's own handshake looks nothing like standard application protocols.

The result:

• A player on a shared IP (university network, corporate VPN, CGNAT) gets flagged because dozens of other users on that IP triggered rate limits — even though the player themselves did nothing wrong
• Players with high packet loss connections (mobile data, satellite internet) retry packets aggressively, which pattern-matches to flood behavior and gets them auto-blocked
• Burst-heavy gameplay (explosions, large vehicle spawns, rapid player joins during a peak hour) can briefly spike UDP rates into ranges the scrubbing center's thresholds consider suspicious
• Geographic rate limits in generic scrubbers throttle entire IP ranges from regions the service considers "high risk", blocking players from those countries entirely

With a generic scrubber, you may stop the DDoS attack but find that 10–20% of your legitimate players can no longer connect — and you have no visibility into why or which players are affected.

Why FiveM-specific proxies handle this better

A proxy built for FiveM can apply context-aware filtering instead of generic thresholds:

• Handshake-first whitelisting — a player's IP isn't rate-limited until they complete FiveM's connection handshake. If the handshake completes, they're whitelisted and their traffic is forwarded without further inspection, regardless of volume
• Per-session rate limits — limits are applied per active session, not per source IP. A player on CGNAT shares an IP with 200 others but has their own session token; their session is evaluated independently
• FiveM traffic signatures — the filter knows what legitimate FiveM packets look like at the byte level and only drops packets that don't match, rather than blocking IPs based on volume alone

The tradeoff is that this approach requires maintaining an accurate model of FiveM's protocol. A generic scrubber applies the same rules to all UDP traffic and ships faster — but players pay for it.

The DIY Route

It is technically possible to set this up yourself:

1. Rent a dedicated server at OVH (they have anti-DDoS included at the infrastructure level)
2. Set up a UDP forward with iptables or nftables
3. Write XDP programs to filter your specific traffic
4. Configure FiveM to accept only that server's IP

This takes days of work, requires solid Linux networking knowledge, and you're on your own when something breaks. OVH's infrastructure-level protection is good but generic — it's not tuned for FiveM's UDP pattern.

The Managed Route

If you don't want to maintain your own proxy infrastructure, the alternative is a managed solution built specifically for FiveM.

fiveshield is what I built after dealing with repeated attacks on my own servers. It handles the proxy infrastructure, XDP filtering, player whitelisting, and IP concealment — with 9+ global proxy locations so players connect through a nearby node.

Setup takes under 5 minutes:

1. Log in with Discord
2. Create a server, choose a proxy location
3. Drop the resource folder into resources/ and add three lines to server.cfg
4. Restart — your origin IP is now hidden and all game traffic is filtered

Pricing is pay-per-player — you're billed daily based on your peak concurrent player count, not a flat monthly fee. A server averaging 10 players costs less than a coffee per day. See the full install guide if you want step-by-step instructions.

Hardening Your Origin Server (Do This Regardless)

Whether you use a proxy or not, apply these regardless:

Block all UDP traffic to your origin IP except from your proxy:

# nftables — only allow game traffic from fiveshield proxy ranges
table inet filter {
  chain input {
    udp dport 30120 ip saddr != { <proxy-ip-ranges> } drop
  }
}

Enable OVH's Game Firewall if you're hosted on OVH — it provides infrastructure-level mitigation that doesn't require your server's CPU to process attack traffic.

Don't publish your origin IP anywhere — not in your Discord, not in error messages, not in debug logs visible to players.

Rotate your origin IP if it's already public. Most VPS providers let you get a new IP for free or a small fee.

Summary

DDoS attacks on FiveM servers are a solved problem — the technology exists. The only question is whether you build the infrastructure yourself or use something that's already built for this purpose.

If you have questions about any of this, feel free to join the fiveshield Discord — happy to help even if you're going the DIY route.