Call of Duty: Modern Warfare 4 Trailer Unveils Game-Changing Anti-Wallhack System

Wallhacks have long been a scourge in Call of Duty, but Modern Warfare 4 aims to put an end to them.

If you're not familiar, wallhacks are cheats that let players see opponents through walls. Call of Duty isn't the only multiplayer game plagued by this, but it's one of the most notorious. That's about to change in Modern Warfare 4.

In a new video on the franchise's official social media, publisher Activision and developer Infinity Ward introduced a system called "server culling" designed to combat wallhack cheaters. The goal is to make Call of Duty: Modern Warfare 4 more reliable and fair than ever.

Few things ruin a match faster than suspecting an opponent saw you through a wall. Wallhacks give cheaters information they shouldn't have. With Modern Warfare 4, we're introducing a new way to fight back: Server Culling. Here's how it… pic.twitter.com/62m41zMbLa

The detailed explanation covers how wallhacks have worked until now. Typically, servers share player location data between game clients, so even if you can't see an enemy behind cover, the game still knows they're there. Server culling, which involved building occlusion layers into Modern Warfare 4's environments, limits information to what the player can actually see. If you can't see someone behind a wall, the backend can't either—and that includes wallhackers.

"For legitimate players, the match plays exactly as intended," Activision explained. "For cheat developers, this creates a major new obstacle."

Server culling will apply to every multiplayer map at launch, and it will also benefit the new DMZ-inspired Combat Outpost mode, Warzone, and future updates. This new tech works alongside existing anti-cheat measures across all platforms.

Activision expects server culling to "disturb the cheat marketplace," but won't "sit on our hands" when it comes to improving the experience. Cheaters have many ways to disrupt matches, and while cheat makers will likely adapt, the publisher vows to stay on top of the issue.

"Cheat software can't reveal information it never receives," the Call of Duty team said in a follow-up post. "When a player shouldn't be able to know where an opponent is, the server can now withhold that opponent's location data from their hardware. It's a new layer in the fight for fair play, working alongside the rest of our anti-cheat systems. Server Culling will cover every map available at launch for MW4."

See you at launch, we'll keep at it

Call of Duty: Modern Warfare 4 launches on October 23, 2026, for PC, Nintendo Switch 2, PlayStation 5, and Xbox Series X/S. How fans will rank it among other installments remains to be seen, but with changes to 2XP tokens and a villain played by Death Stranding and Casino Royale actor Mads Mikkelsen, it's clear the developers are pulling out all the stops.

For more, read about how the series' anti-cheat boss pushed back on cheating myths, and how much Activision estimates the cheating market generates annually.