Gunter Höckel 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.
The problem can be corrected by updating your system to the following package versions:
5 January 2009
A security issue affects these releases of Ubuntu and its derivatives:
Gunter Höckel 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.
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system upgrade is sufficient to effect the necessary changes.
Vulmon