CentOS 6 : samba4 (CESA-2016:0010)

2016-01-08T00:00:00
ID CENTOS_RHSA-2016-0010.NASL
Type nessus
Reporter Tenable
Modified 2018-11-10T00:00:00

Description

Updated samba4 packages that fix multiple security issues are now available for Red Hat Enterprise Linux 6.

Red Hat Product Security has rated this update as having Moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

Samba is an open source implementation of the Server Message Block (SMB) or Common Internet File System (CIFS) protocol, which allows PC-compatible machines to share files, printers, and other information.

A denial of service flaw was found in the LDAP server provided by the AD DC in the Samba process daemon. A remote attacker could exploit this flaw by sending a specially crafted packet, which could cause the server to consume an excessive amount of memory and crash. (CVE-2015-7540)

Multiple buffer over-read flaws were found in the way Samba handled malformed inputs in certain encodings. An authenticated, remote attacker could possibly use these flaws to disclose portions of the server memory. (CVE-2015-5330)

A man-in-the-middle vulnerability was found in the way 'connection signing' was implemented by Samba. A remote attacker could use this flaw to downgrade an existing Samba client connection and force the use of plain text. (CVE-2015-5296)

A missing access control flaw was found in Samba. A remote, authenticated attacker could use this flaw to view the current snapshot on a Samba share, despite not having DIRECTORY_LIST access rights. (CVE-2015-5299)

An access flaw was found in the way Samba verified symbolic links when creating new files on a Samba share. A remote attacker could exploit this flaw to gain access to files outside of Samba's share path. (CVE-2015-5252)

Red Hat would like to thank the Samba project for reporting these issues. Upstream acknowledges Stefan Metzmacher of the Samba Team and Sernet.de as the original reporters of CVE-2015-5296, partha@exablox.com as the original reporter of CVE-2015-5299, Jan 'Yenya' Kasprzak and the Computer Systems Unit team at Faculty of Informatics, Masaryk University as the original reporters of CVE-2015-5252 flaws, and Douglas Bagnall as the original reporter of CVE-2015-5330.

All samba4 users are advised to upgrade to these updated packages, which contain backported patches to correct these issues. After installing this update, the smb service will be restarted automatically.

                                        
                                            #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Red Hat Security Advisory RHSA-2016:0010 and 
# CentOS Errata and Security Advisory 2016:0010 respectively.
#

include("compat.inc");

if (description)
{
  script_id(87783);
  script_version("2.9");
  script_cvs_date("Date: 2018/11/10 11:49:31");

  script_cve_id("CVE-2015-5252", "CVE-2015-5296", "CVE-2015-5299", "CVE-2015-5330", "CVE-2015-7540");
  script_xref(name:"RHSA", value:"2016:0010");

  script_name(english:"CentOS 6 : samba4 (CESA-2016:0010)");
  script_summary(english:"Checks rpm output for the updated packages");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote CentOS host is missing one or more security updates."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Updated samba4 packages that fix multiple security issues are now
available for Red Hat Enterprise Linux 6.

Red Hat Product Security has rated this update as having Moderate
security impact. Common Vulnerability Scoring System (CVSS) base
scores, which give detailed severity ratings, are available for each
vulnerability from the CVE links in the References section.

Samba is an open source implementation of the Server Message Block
(SMB) or Common Internet File System (CIFS) protocol, which allows
PC-compatible machines to share files, printers, and other
information.

A denial of service flaw was found in the LDAP server provided by the
AD DC in the Samba process daemon. A remote attacker could exploit
this flaw by sending a specially crafted packet, which could cause the
server to consume an excessive amount of memory and crash.
(CVE-2015-7540)

Multiple buffer over-read flaws were found in the way Samba handled
malformed inputs in certain encodings. An authenticated, remote
attacker could possibly use these flaws to disclose portions of the
server memory. (CVE-2015-5330)

A man-in-the-middle vulnerability was found in the way 'connection
signing' was implemented by Samba. A remote attacker could use this
flaw to downgrade an existing Samba client connection and force the
use of plain text. (CVE-2015-5296)

A missing access control flaw was found in Samba. A remote,
authenticated attacker could use this flaw to view the current
snapshot on a Samba share, despite not having DIRECTORY_LIST access
rights. (CVE-2015-5299)

An access flaw was found in the way Samba verified symbolic links when
creating new files on a Samba share. A remote attacker could exploit
this flaw to gain access to files outside of Samba's share path.
(CVE-2015-5252)

Red Hat would like to thank the Samba project for reporting these
issues. Upstream acknowledges Stefan Metzmacher of the Samba Team and
Sernet.de as the original reporters of CVE-2015-5296,
partha@exablox.com as the original reporter of CVE-2015-5299, Jan
'Yenya' Kasprzak and the Computer Systems Unit team at Faculty of
Informatics, Masaryk University as the original reporters of
CVE-2015-5252 flaws, and Douglas Bagnall as the original reporter of
CVE-2015-5330.

All samba4 users are advised to upgrade to these updated packages,
which contain backported patches to correct these issues. After
installing this update, the smb service will be restarted
automatically."
  );
  # https://lists.centos.org/pipermail/centos-announce/2016-January/021599.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?ed558323"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected samba4 packages."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4-client");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4-dc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4-dc-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4-pidl");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4-python");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4-swat");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4-test");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4-winbind");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4-winbind-clients");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:samba4-winbind-krb5-locator");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:centos:centos:6");

  script_set_attribute(attribute:"patch_publication_date", value:"2016/01/07");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/01/08");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2018 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"CentOS Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/CentOS/release", "Host/CentOS/rpm-list");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("rpm.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/CentOS/release")) audit(AUDIT_OS_NOT, "CentOS");
if (!get_kb_item("Host/CentOS/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);


cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "CentOS", cpu);


flag = 0;
if (rpm_check(release:"CentOS-6", reference:"samba4-4.0.0-67.el6_7.rc4")) flag++;
if (rpm_check(release:"CentOS-6", reference:"samba4-client-4.0.0-67.el6_7.rc4")) flag++;
if (rpm_check(release:"CentOS-6", reference:"samba4-common-4.0.0-67.el6_7.rc4")) flag++;
if (rpm_check(release:"CentOS-6", reference:"samba4-dc-4.0.0-67.el6_7.rc4")) flag++;
if (rpm_check(release:"CentOS-6", reference:"samba4-dc-libs-4.0.0-67.el6_7.rc4")) flag++;
if (rpm_check(release:"CentOS-6", reference:"samba4-devel-4.0.0-67.el6_7.rc4")) flag++;
if (rpm_check(release:"CentOS-6", reference:"samba4-libs-4.0.0-67.el6_7.rc4")) flag++;
if (rpm_check(release:"CentOS-6", reference:"samba4-pidl-4.0.0-67.el6_7.rc4")) flag++;
if (rpm_check(release:"CentOS-6", reference:"samba4-python-4.0.0-67.el6_7.rc4")) flag++;
if (rpm_check(release:"CentOS-6", reference:"samba4-swat-4.0.0-67.el6_7.rc4")) flag++;
if (rpm_check(release:"CentOS-6", reference:"samba4-test-4.0.0-67.el6_7.rc4")) flag++;
if (rpm_check(release:"CentOS-6", reference:"samba4-winbind-4.0.0-67.el6_7.rc4")) flag++;
if (rpm_check(release:"CentOS-6", reference:"samba4-winbind-clients-4.0.0-67.el6_7.rc4")) flag++;
if (rpm_check(release:"CentOS-6", reference:"samba4-winbind-krb5-locator-4.0.0-67.el6_7.rc4")) flag++;


if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:rpm_report_get());
  else security_warning(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");