USN-918-1: Samba vulnerability

24 March 2010

Samba vulnerability

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Releases

Packages

Details

It was discovered the Samba handled symlinks in an unexpected way when both
"wide links" and "UNIX extensions" were enabled, which is the default. A
remote attacker could create symlinks and access arbitrary files from the
server.

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 9.10
Ubuntu 9.04
Ubuntu 8.10
Ubuntu 8.04
Ubuntu 6.06

In general, a standard system upgrade is sufficient to effect the
necessary changes.

ATTENTION: This update changes the default samba behaviour. For security
reasons, it is no longer possible to use wide links and UNIX extensions at
the same time. After applying this security update, wide links will be
disabled automatically as UNIX extensions are turned on by default. If
wide links are required, you can re-enable them by adding
"unix extensions = no" to the [global] section of the /etc/samba/smb.conf
configuration file.

References