Red Hat Security Advisory 2012-0313-03 - Samba is an open-source implementation of the Server Message Block or Common Internet File System protocol, which allows PC-compatible machines to share files, printers, and other information. The default Samba server configuration enabled both the "wide links" and "unix extensions" options, allowing Samba clients with write access to a share to create symbolic links that point to any location on the file system. Clients connecting with CIFS UNIX extensions disabled could have such links resolved on the server, allowing them to access and possibly overwrite files outside of the share. With this update, "wide links" is set to "no" by default. In addition, the update ensures "wide links" is disabled for shares that have "unix extensions" enabled.