Jul 11, 2017
Left 4 Dead 2 - Update
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Fixed a crash in particle systems loaded from Add-ons.
Jun 30, 2017
Left 4 Dead 2 - Update
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Fixed security issues reported by Justin Taft from One Up Security, LLC.
May 30, 2017
Left 4 Dead 2 - Update
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Fixed a potential remote code execution exploit.
May 30, 2017
Left 4 Dead - Update
Left 4 Dead - Valve
An update has been released for Left 4 Dead.

- Fixed a potential remote code execution exploit.
Jan 25, 2017
Left 4 Dead 2 - Update
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 - Update
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.
Jun 3, 2016
Left 4 Dead 2 - Update
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.
May 4, 2016
Left 4 Dead 2 - Update
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.
Mar 24, 2016
Left 4 Dead - Update
Left 4 Dead - Valve
An update has been released for Left 4 Dead.

- Fixed exploits that could allow remote code execution.
- Remove forced shutdown when ctrl-alt-del is pressed.
- Protect against a reported crash caused by a map name parsing failure.
- Protect against a reported crash when returning to a lobby.
Feb 23, 2016
Left 4 Dead - Update
Left 4 Dead - Valve
An update has been released for Left 4 Dead.

- Updated binaries to improve crash reports.
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