Vulnerability in roblox's backpack/tool system can allow players to noclip for an instant

Roblox’s tool/backpack system currently has a vulnerability that allows players to noclip through walls in games that have the default roblox backpack/tool system. All you have to do is have one tool, use the repro steps, and you can phase through parts momentarily. In this state, you can walk through any part/parts.

Note: This does require an external program to be able to do, and I’ve submitted the repro steps and videos/pictures to the exploit reports group.
Note 2: If you would like me to post pictures and videos here, let me know (they reveal how its done so i thought i shouldn’t

The bug happens in any game that has the default roblox tool/backpack system and at least one tool given to the player by the server/starterpack. The tool must have have a handle/physical form as it uses collision glitches to allow phasisg. During the “phase” the player’s HumanoidStateType becomes RunningNoPhysics thus allowing noclip as “no physics” is applied to the character.

Unsure of when it started happening, but it can be successfully reproduced since 5/26/2020.


Hello, if you’d like a temporary fix for this, I’d suggest using AncestryChanged on tools and checking it server-side to see if players are abusing this unintended behavior. Also, this bug does not apply to all tools, I believe it’s really dependent on how the tools are built (from my testing).

I believe (from testing) that it is more due to the tool equip animations. Even tools without handles but with a custom idle animation are affected by this, for example the Fists tool in The Streets. I may be wrong, though.