: Restricting dupe uploading or spawning to trusted players and using IP or SteamID bans for offenders. Possible Server Crashing Paste Bug · Issue #45 - GitHub
Because a successful crasher dupe terminates the server instance, local in-game logs may become corrupted or unreadable. Use an external logging system or a server control panel (like Pterodactyl or TCAdmin) that streams console logs in real-time. Look for a massive spike in spawned entities from a single SteamID right before the connection drops to identify the attacker. Conclusion
Since constraints require the server to maintain constant attachment data, malicious dupes can abuse this. A common method is known as "Multi-Parenting," where a prop is forced to be the parent of multiple objects simultaneously—a mathematical impossibility that leads directly to a server crash. gmod server crasher dupe verified
Spawning thousands of constrained entities (props, thrusters, lamps) instantly.
GMod relies heavily on "net messages" to communicate data between the client and the server. Malicious players use Lua scripts to spam massive, poorly optimized net strings. If a server addon is written without strict rate-limits, processing thousands of these requests per second will instantly freeze the server's CPU. 2. Physics Engine Overload (Prop Spawning) : Restricting dupe uploading or spawning to trusted
Before we discuss the crash, we must understand the container. In GMod, a "dupe" (short for Duplicate) is a saved construction. Players use the tool or the built-in Duplicator tool to save complex contraptions—bases, wiremod computers, or hovercrafts—to their local files. These files ( .txt or .dupe ) contain all the props, constraints, and scripts needed to spawn the creation instantly.
: Servers often limit the number of props that can be spawned in a single dupe or use "slow-pasting" features to spawn items one by one rather than all at once. Blacklisting Look for a massive spike in spawned entities
More sophisticated exploits involve actual memory corruption. Some crash methods exploit the Source engine's memory handling, such as the use of gmod_unload_test 1 with broken func_breakable_surf entities causing instant crashes on dedicated servers.