Updates to Left 4 Dead have been released. The updates will be applied automatically when your Steam client is restarted. The specific changes include:

Engine

• Fixed an exploit that allowed files to be uploaded to the server at arbitrary locations in the file system


• Fixed a server crash caused by a client packet claiming to be an HLTV client when HLTV is disabled on the server


• Fixed a server crash caused by spoofing a client disconnect message


• Fixed a server crash caused by sending malformed reliable subchannel data

Left 4 Dead

• Novint Falcon support is now enabled by default