RHEL 6 : kernel (RHSA-2015:1643)

2015-08-19T00:00:00
ID REDHAT-RHSA-2015-1643.NASL
Type nessus
Reporter Tenable
Modified 2018-11-10T00:00:00

Description

Updated kernel packages that fix one security issue and two bugs are now available for Red Hat Enterprise Linux 6.4 Advanced Update Support.

Red Hat Product Security has rated this update as having Moderate security impact. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available from the CVE link in the References section.

The kernel packages contain the Linux kernel, the core of any Linux operating system.

  • It was found that the Linux kernel's ping socket implementation did not properly handle socket unhashing during spurious disconnects, which could lead to a use-after-free flaw. On x86-64 architecture systems, a local user able to create ping sockets could use this flaw to crash the system. On non-x86-64 architecture systems, a local user able to create ping sockets could use this flaw to escalate their privileges on the system. (CVE-2015-3636, Moderate)

This update also fixes the following bugs :

  • Due to bad memory or memory corruption, an isolated BUG_ON(mm->nr_ptes) was sometimes reported, indicating that not all the page tables allocated could be found and freed when the exit_mmap() function cleared the user address space. As a consequence, a kernel panic occurred. To fix this bug, the BUG_ON() function has been replaced by WARN_ON(), which prevents the kernel from panicking in the aforementioned situation. (BZ#1235929)

  • Previously, it was for the ext4 driver to read a metadata block and use it without a verification. If the metadata block was corrupted, a kernel panic could occur. With this update, verification is forced on every buffer before it is used, which uncovers possible corruption and prevents further use of the corrupted metadata buffer. (BZ#1242930)

All kernel users are advised to upgrade to these updated packages, which contain backported patches to correct these issues. The system must be rebooted for this update to take effect.

                                        
                                            #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Red Hat Security Advisory RHSA-2015:1643. The text 
# itself is copyright (C) Red Hat, Inc.
#

include("compat.inc");

if (description)
{
  script_id(85531);
  script_version("2.7");
  script_cvs_date("Date: 2018/11/10 11:49:54");

  script_cve_id("CVE-2015-3636");
  script_xref(name:"RHSA", value:"2015:1643");

  script_name(english:"RHEL 6 : kernel (RHSA-2015:1643)");
  script_summary(english:"Checks the rpm output for the updated packages");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Red Hat host is missing one or more security updates."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Updated kernel packages that fix one security issue and two bugs are
now available for Red Hat Enterprise Linux 6.4 Advanced Update
Support.

Red Hat Product Security has rated this update as having Moderate
security impact. A Common Vulnerability Scoring System (CVSS) base
score, which gives a detailed severity rating, is available from the
CVE link in the References section.

The kernel packages contain the Linux kernel, the core of any Linux
operating system.

* It was found that the Linux kernel's ping socket implementation did
not properly handle socket unhashing during spurious disconnects,
which could lead to a use-after-free flaw. On x86-64 architecture
systems, a local user able to create ping sockets could use this flaw
to crash the system. On non-x86-64 architecture systems, a local user
able to create ping sockets could use this flaw to escalate their
privileges on the system. (CVE-2015-3636, Moderate)

This update also fixes the following bugs :

* Due to bad memory or memory corruption, an isolated
BUG_ON(mm->nr_ptes) was sometimes reported, indicating that not all
the page tables allocated could be found and freed when the
exit_mmap() function cleared the user address space. As a consequence,
a kernel panic occurred. To fix this bug, the BUG_ON() function has
been replaced by WARN_ON(), which prevents the kernel from panicking
in the aforementioned situation. (BZ#1235929)

* Previously, it was for the ext4 driver to read a metadata block and
use it without a verification. If the metadata block was corrupted, a
kernel panic could occur. With this update, verification is forced on
every buffer before it is used, which uncovers possible corruption and
prevents further use of the corrupted metadata buffer. (BZ#1242930)

All kernel users are advised to upgrade to these updated packages,
which contain backported patches to correct these issues. The system
must be rebooted for this update to take effect."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/errata/RHSA-2015:1643"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/security/cve/cve-2015-3636"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:N/I:N/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/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:redhat:enterprise_linux:kernel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-debug");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-debug-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-debug-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-debuginfo-common-x86_64");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-firmware");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-headers");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:perf");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:perf-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:python-perf");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:python-perf-debuginfo");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:6.4");

  script_set_attribute(attribute:"patch_publication_date", value:"2015/08/18");
  script_set_attribute(attribute:"plugin_publication_date", value:"2015/08/19");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2015-2018 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Red Hat Local Security Checks");

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

  exit(0);
}


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

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/RedHat/release");
if (isnull(release) || "Red Hat" >!< release) audit(AUDIT_OS_NOT, "Red Hat");
os_ver = eregmatch(pattern: "Red Hat Enterprise Linux.*release ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Red Hat");
os_ver = os_ver[1];
if (! ereg(pattern:"^6\.4([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Red Hat 6.4", "Red Hat " + os_ver);

if (!get_kb_item("Host/RedHat/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$" && "s390" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Red Hat", cpu);

yum_updateinfo = get_kb_item("Host/RedHat/yum-updateinfo");
if (!empty_or_null(yum_updateinfo)) 
{
  rhsa = "RHSA-2015:1643";
  yum_report = redhat_generate_yum_updateinfo_report(rhsa:rhsa);
  if (!empty_or_null(yum_report))
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : yum_report 
    );
    exit(0);
  }
  else
  {
    audit_message = "affected by Red Hat security advisory " + rhsa;
    audit(AUDIT_OS_NOT, audit_message);
  }
}
else
{
  flag = 0;
  if (rpm_check(release:"RHEL6", sp:"4", cpu:"x86_64", reference:"kernel-2.6.32-358.65.1.el6")) flag++;
  if (rpm_check(release:"RHEL6", sp:"4", cpu:"x86_64", reference:"kernel-debug-2.6.32-358.65.1.el6")) flag++;
  if (rpm_check(release:"RHEL6", sp:"4", cpu:"x86_64", reference:"kernel-debug-debuginfo-2.6.32-358.65.1.el6")) flag++;
  if (rpm_check(release:"RHEL6", sp:"4", cpu:"x86_64", reference:"kernel-debug-devel-2.6.32-358.65.1.el6")) flag++;
  if (rpm_check(release:"RHEL6", sp:"4", cpu:"x86_64", reference:"kernel-debuginfo-2.6.32-358.65.1.el6")) flag++;
  if (rpm_check(release:"RHEL6", sp:"4", cpu:"x86_64", reference:"kernel-debuginfo-common-x86_64-2.6.32-358.65.1.el6")) flag++;
  if (rpm_check(release:"RHEL6", sp:"4", cpu:"x86_64", reference:"kernel-devel-2.6.32-358.65.1.el6")) flag++;
  if (rpm_check(release:"RHEL6", sp:"4", reference:"kernel-doc-2.6.32-358.65.1.el6")) flag++;
  if (rpm_check(release:"RHEL6", sp:"4", reference:"kernel-firmware-2.6.32-358.65.1.el6")) flag++;
  if (rpm_check(release:"RHEL6", sp:"4", cpu:"x86_64", reference:"kernel-headers-2.6.32-358.65.1.el6")) flag++;
  if (rpm_check(release:"RHEL6", sp:"4", cpu:"x86_64", reference:"perf-2.6.32-358.65.1.el6")) flag++;
  if (rpm_check(release:"RHEL6", sp:"4", cpu:"x86_64", reference:"perf-debuginfo-2.6.32-358.65.1.el6")) flag++;
  if (rpm_check(release:"RHEL6", sp:"4", cpu:"x86_64", reference:"python-perf-2.6.32-358.65.1.el6")) flag++;
  if (rpm_check(release:"RHEL6", sp:"4", cpu:"x86_64", reference:"python-perf-debuginfo-2.6.32-358.65.1.el6")) flag++;

  if (flag)
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : rpm_report_get() + redhat_report_package_caveat()
    );
    exit(0);
  }
  else
  {
    tested = pkg_tests_get();
    if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
    else audit(AUDIT_PACKAGE_NOT_INSTALLED, "kernel / kernel-debug / kernel-debug-debuginfo / kernel-debug-devel / etc");
  }
}