RHSA-2009:1529 - Security Advisory

Topic

Updated samba packages that fix multiple security issues are now available
for Red Hat Enterprise Linux 4 and 5.

This update has been rated as having moderate security impact by the Red
Hat Security Response Team.

Description

Samba is a suite of programs used by machines to share files, printers, and
other information.

A denial of service flaw was found in the Samba smbd daemon. An
authenticated, remote user could send a specially-crafted response that
would cause an smbd child process to enter an infinite loop. An
authenticated, remote user could use this flaw to exhaust system resources
by opening multiple CIFS sessions. (CVE-2009-2906)

An uninitialized data access flaw was discovered in the smbd daemon when
using the non-default "dos filemode" configuration option in "smb.conf". An
authenticated, remote user with write access to a file could possibly use
this flaw to change an access control list for that file, even when such
access should have been denied. (CVE-2009-1888)

A flaw was discovered in the way Samba handled users without a home
directory set in the back-end password database (e.g. "/etc/passwd"). If a
share for the home directory of such a user was created (e.g. using the
automated "[homes]" share), any user able to access that share could see
the whole file system, possibly bypassing intended access restrictions.
(CVE-2009-2813)

The mount.cifs program printed CIFS passwords as part of its debug output
when running in verbose mode. When mount.cifs had the setuid bit set, a
local, unprivileged user could use this flaw to disclose passwords from a
file that would otherwise be inaccessible to that user. Note: mount.cifs
from the samba packages distributed by Red Hat does not have the setuid bit
set. This flaw only affected systems where the setuid bit was manually set
by an administrator. (CVE-2009-2948)

Users of Samba should upgrade to these updated packages, which contain
backported patches to correct these issues. After installing this update,
the smb service will be restarted automatically.

Solution

Before applying this update, make sure that all previously-released
errata relevant to your system have been applied.

This update is available via Red Hat Network. Details on how to use
the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Server 4 x86_64
• Red Hat Enterprise Linux Server 4 ia64
• Red Hat Enterprise Linux Server 4 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.4 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.4 ia64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.4 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 4.8 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 4.8 ia64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 4.8 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Workstation 4 x86_64
• Red Hat Enterprise Linux Workstation 4 ia64
• Red Hat Enterprise Linux Workstation 4 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux Desktop 4 x86_64
• Red Hat Enterprise Linux Desktop 4 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for IBM z Systems 4 s390x
• Red Hat Enterprise Linux for IBM z Systems 4 s390
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 5.4 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 4.8 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 4.8 s390
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux for Power, big endian 4 ppc
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 5.4 ppc
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 4.8 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386

Fixes

• BZ - 506996 - CVE-2009-1888 Samba improper file access
• BZ - 523752 - CVE-2009-2813 Samba: Share restriction bypass via home-less directory user account(s)
• BZ - 526074 - CVE-2009-2948 samba: information disclosure in suid mount.cifs
• BZ - 526645 - CVE-2009-2906 samba: infinite loop flaw in smbd on unexpected oplock break notification reply

CVEs

• CVE-2009-2906
• CVE-2009-1888
• CVE-2009-2813
• CVE-2009-2948

References

• http://www.redhat.com/security/updates/classification/#moderate