The GMod crasher dupe is a fascinating example of emergent exploits in a physics sandbox—but fascinating stops being fun when your 50-player server evaporates at 2 AM.
Secure your prop limits. Lock down Wiremod. And for the love of all that is unconstrained, make backups.
Stay safe out there, builders.
— ByteStorm
Have you encountered a crasher dupe on your server? Let us know in the comments what worked for stopping it.
SERVER CRASHER DUPE: GAMEMODE.EXPLOIT.PROPBOMB
Hey fellow exploiters,
I just found a crazy server crasher dupe in Garry's Mod that can take down even the most stable servers. Introducing... PropBomb 2.0!
How it works:
BOOM
Servers will crash instantly due to an infinite recursion in the physics engine. Easy to execute and devastatingly effective.
Requirements:
Example Use Case:
Imagine you're an admin on a public server, and you want to troll the server owners. Just execute the exploit, and watch as the server crashes.
Notes:
DM me if you want more info or want to contribute to the exploit.
Don't say I didn't warn you...
(Disclaimer: please don't actually post this on a public forum or use it to harm servers; just a hypothetical example.)
Garry’s Mod , "server crasher" dupes are designed to overload a server's resources—specifically CPU and RAM—until the server hangs or crashes
. Creating these often involves exploiting physics engine limits or entity limits. How to Create a Basic Dupe
To create and save any duplication (dupe) in GMod, including those designed for high resource usage: Dupes designed to crash servers? - Garry's Mod
Garry’s Mod (GMod) , a "server crasher dupe" typically refers to a saved creation (dupe) designed to overwhelm a server's resources, causing it to lag, freeze, or crash upon being spawned
. While these are often used maliciously, understanding how they work is key for server owners to protect their communities. Steam Community Common Methods & Mechanics
"Crasher" dupes generally exploit the way the game handles large amounts of data or physics calculations in a single frame:
: Dupes containing hundreds or thousands of props that exceed the server's entity limits. Physics Overload
: Using "illegal" constraints (like thousands of ropes, welds, or elastic connections) that cause a massive physics calculation spike. Net Message Overloading : Advanced dupes using Expression 2 (E2) chips that spam the server with networked data. Invalid Entities
: Spawning objects that no longer exist in the server's files or were created using a bugged duplication process. Prevention for Server Owners
To keep your server stable, you can implement the following protections: Advanced Duplicator 2 (AdvDupe2) Settings
: This popular addon allows admins to disable "dupe uploading," preventing players from bringing in external files. Prop & Entity Limits : Configure sbox_maxprops gmod server crasher dupe
and other limit commands to restrict how many items can be spawned at once. Delayed Spawning Addons : Tools like Better Dupe
force dupes to spawn props over a period of time rather than all at once, preventing "single-tick" lag spikes. Blacklisting
: Use administrative tools (like ULX or FPP) to blacklist specific problematic props or entities that are frequently used in crashers. Net Message Loggers
: For technical exploits, using a logger can help identify which player or addon is sending excessive data to the server. General Stability Tips
If your own game or server is crashing frequently during normal play: Verify Integrity : Use Steam to verify game files to ensure no core assets are corrupted. Driver Updates : Ensure your graphics drivers are up to date. Clear Cache : Periodically delete the garrysmod/cache garrysmod/downloads folders to remove old, potentially conflicting assets. admin tools to block these dupes, or are you trying to troubleshoot a specific crash you've experienced?
Possible Server Crashing Paste Bug · Issue #45 · wiremod/advdupe2 16-Mar-2015 —
Creating or using "server crasher" duplications (dupes) is generally considered a form of griefing and is against the Terms of Service Garry's Mod servers and the Steam Workshop
. Such dupes are designed to exploit game physics or entity limits to intentionally lag or crash a server.
If you are looking to learn how to manage and use legitimate duplications for building and creative purposes, here is a guide on using the standard and advanced tools: Using the Standard Duplicator standard Duplicator tool
is built into Garry's Mod and is used for copying simple structures. Garry's Mod Wiki | Fandom : Select the Duplicator
tool from the "Tools" tab in the "Q" menu. Right-click on a prop to copy it and everything welded or parented to it. : Left-click on any surface to spawn the copied structure. : Open the "Q" menu, go to the tab, and click to store your creation locally. Using Advanced Duplicator 2 (AdvDupe2) Many servers use the Advanced Duplicator 2
addon because it handles complex constraints and large builds more reliably. : You can copy large areas by setting the Area Copy Size in the tool settings. Hold
while right-clicking to select all entities within that green radius. Saving Files Open the AdvDupe2 menu. Right-click a folder in the file browser. , enter a name, and confirm.
: Double-click a saved file in your folder list to load it into your tool, then left-click in the world to paste. Server Stability Tips The GMod crasher dupe is a fascinating example
If you are trying to prevent your own server from being crashed by malicious dupes, consider these official Garry's Mod wiki recommendations: Entity Limits
: Set strict limits for props, effects, and ragdolls in your server config ( sbox_maxprops Anticrash Addons : Install tools like APG (Anti-Prop Griefing)
to automatically detect and remove entities that cause physics lag. Whitelist Dupes
: Restrict the use of the Duplicator tool to trusted ranks (e.g., Donors or Staff) using admin mods like tools or how to optimize physics settings to prevent lag?
Here’s a post you could use to warn or inform others about GMod server crasher dupes. I’ve written it in an informative, PSA-style tone — suitable for a forum, Discord server, or Steam group.
🚨 PSA: GMod Server Crasher Dupes – What You Need to Know 🚨
Lately, there’s been an increase in server-crasher dupes circulating in Garry’s Mod — especially in Sandbox, DarkRP, and Prop Hunt servers.
These dupes are not just annoying — they can:
Many older crash dupes rely on bugs patched in 2020–2022. If you’re still on GMod version from 2018, you’re a target.
Crasher dupes usually contain:
A crasher dupe exploits one of three core vulnerabilities in GMod’s physics or networking engine. Modern crash dupes fall into three main categories:
If you’re tempted to crash a server because an admin abused you, or because you think it’s funny, consider the following:
Before major patches in 2018-2020, some dupes could embed raw Lua code using the Advanced Dupe 2 tool. A crasher dupe might contain:
while true do
game.GetAllPlayers()[1]:Kill()
end
Or worse, a function that creates thousands of networked entities, leading to a buffer overflow crash. While modern GMod has largely patched direct Lua injection via dupes, old servers running outdated addons remain vulnerable. BOOM Servers will crash instantly due to an
Here’s the frustrating part: The dupe itself isn’t malware. It’s a .txt or .dat file containing positions, angles, and entity types.
By the time you realize it was a crasher, the damage is done.