Mandriva Linux Security Advisory 2009-042 - Samba 3.2.0 through 3.2.6, when registry shares are enabled, allows remote authenticated users to access the root filesystem via a crafted connection request that specifies a blank share name. This update provides samba 3.2.7 to address this issue.
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Ubuntu Security Notice USN-702-1 - Gunter Hockel discovered that Samba with registry shares enabled did not properly validate share names. An authenticated user could gain access to the root filesystem by using an older version of smbclient and specifying an empty string as a share name. This is only an issue if registry shares are enabled on the server by setting "registry shares = yes", "include = registry", or "config backend = registry", which is not the default.
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