RHSA-2009:1585 - Security Advisory

トピック

Updated samba3x packages that fix multiple security issues and various bugs
are now available for Red Hat Enterprise Linux 5 Supplementary.

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

説明

Samba is a suite of programs used by machines to share files, printers, and
other information. These samba3x packages provide Samba 3.3, which is a
Technology Preview for Red Hat Enterprise Linux 5. These packages cannot be
installed in parallel with the samba packages. Note: Technology Previews
are not intended for production use.

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 samba3x 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)

This update also fixes the following bugs:

• the samba3x packages contained missing and conflicting license

information. License information was missing for the libtalloc, libtdb, and
tdb-tools packages. The samba3x-common package provided a COPYING file;
however, it stated the license was GPLv2, while RPM metadata stated the
licenses were either GPLv3 or LGPLv3. This update adds the correct
licensing information to the samba3x-common, libsmbclient, libtalloc,
libtdb, and tdb-tools packages. (BZ#528633)

• the upstream Samba version in the samba3x packages distributed with the

RHEA-2009:1399 update contained broken implementations of the Netlogon
credential chain and SAMR access checks security subsystems. This prevented
Samba from acting as a domain controller: Client systems could not join the
domain; users could not authenticate; and systems could not access the user
and group list. (BZ#524551)

• this update resolves interoperability issues with Windows 7 and Windows

Server 2008 R2. (BZ#529022)

These packages upgrade Samba from version 3.3.5 to version 3.3.8. Refer to
the Samba Release Notes for a list of changes between versions:
http://samba.org/samba/history/

Users of samba3x should upgrade to these updated packages, which resolve
these issues. After installing this update, the smb service will be
restarted automatically.

解決策

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

影響を受ける製品

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.4 x86_64
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 x86_64

修正

• 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 - 524551 - samba3x 3.3.4 is broken as domain controller
• 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
• BZ - 528633 - License problem for Samba3X in x86_64 supplementary image
• BZ - 529022 - Interoperation with Windows 7 and Windows 2008 (R2) broken

CVE

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

参考資料

• http://www.redhat.com/security/updates/classification/#moderate
• http://www.redhat.com/support/policy/soc/production/preview_scope/
• http://samba.org/samba/history/