Jan 25, 2017
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Fixed a server lagging exploit.
- Fixed some reported security exploits.
- Fixed key bindings not displaying correctly when using the Xbox 360 controller.

New EMS scripting features:
- Added a new interface for reading/writing entity network and data table fields from script. Use "script_help NetProp" for interface details.
- New script function "TakeDamage( amount, type, attacker )".
- New script function "GetNetworkIDString()".
- Added "timeofday" keyfield to the world entity.
- Support auto_spawn of witch bride.
Jun 28, 2016
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Fixed an issue on some MacBook Pro models that prevented the game from rendering correctly, resulting in a blank or white screen with game running in the background. This fix required a change to the minimum spec from MacOS 10.6.4 to MacOS 10.7 (Lion) or higher, which matches Steam's minimum spec.
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Fixed multiple potential remote code execution exploits.
- Speculative fix for Mac startup rendering issue.
- Updated Steam API version.
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Fixed two exploits that could allow remote code execution on clients and servers.
- Disabled some debug tracking that was causing a crash.
Feb 18, 2016
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Fixed an exploit where a player could call a vote that would pass immediately without input from the rest of the players.
- Fixed an issue where sounds could start looping on Linux.
- Fixed Steam Controller issues with spectating and MOTD.
- Fixed a bug that could cause some servers to hang on shutdown, causing a temporary reduction in total server capacity after updates.
- Fixed a remote code execution exploit.
- Upgrade OSX SDK version.
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Fixed two exploits that could allow remote code execution.
- Fixed controller navigation of some lobby settings menus.
Dec 18, 2015
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2:

- Added haptics support for Steam Controllers
Dec 16, 2015
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2:

- Fixed Options menu cutting off Steam Cloud option.
Dec 10, 2015
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Fixed some Steam Controller bugs
- Added bindings for voting with the Steam Controller
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2 Authoring Tools.

- Fixed Workshop Manager failing to launch.
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