July 2017 Hotfix #2

We've had a bunch of recent crash reports that were caused by specific models with invalid flex rules. These crashes could have been triggered by addons that utilise model flexes, voice chat mouth movement, or the faceposer tool. This shouldn't happen any more.

You can read about the vulnerability in the Source Engine that was discovered by One Up Security here. This is now fixed in Garry's Mod.