Jun Mao discovered that Samba, an implementation of the SMB/CIFS protocol
for Unix systems, is not properly handling certain offset values when
processing chained SMB1 packets. This enables an unauthenticated attacker
to write to an arbitrary memory location resulting in the possibility to
execute arbitrary code with root privileges or to perform denial of service
attacks by crashing the samba daemon.

For the stable distribution (lenny), this problem has been fixed in
version 3.2.5-4lenny12.

This problem does not affect the versions in the testing (squeeze) and
unstable (sid) distribution.

We recommend that you upgrade your samba packages.