An update has been released for Left 4 Dead. - Fixed an exploit that could shut down dedicated servers. - Fixed several buffer overflow exploits with networked files. - Fixed a series of exploits caused by invalid or malformed textures.
Dirty hack applied. Just modified the server version to 1.0.3.0 Should work. The normal/old update does not work anymore. It is steamcmd now (already since the last update) but I did not make the update because of incompatible plugins.