CentOS 6 : kernel (CESA-2019:2473)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Red Hat Security Advisory RHSA-2019:2473 and 
# CentOS Errata and Security Advisory 2019:2473 respectively.
#

include("compat.inc");

if (description)
{
  script_id(127919);
  script_version("1.5");
  script_cvs_date("Date: 2020/02/18");

  script_cve_id("CVE-2017-17805", "CVE-2018-17972", "CVE-2019-1125", "CVE-2019-5489");
  script_xref(name:"RHSA", value:"2019:2473");

  script_name(english:"CentOS 6 : kernel (CESA-2019:2473)");
  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:
"An update for kernel is now available for Red Hat Enterprise Linux 6.

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

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

Security Fix(es) :

* Kernel: page cache side channel attacks (CVE-2019-5489)

* kernel: Salsa20 encryption algorithm does not correctly handle
zero-length inputs allowing local attackers to cause denial-of-service
(CVE-2017-17805)

* kernel: Unprivileged users able to inspect kernel stacks of
arbitrary tasks (CVE-2018-17972)

* kernel: hw: Spectre SWAPGS gadget vulnerability (CVE-2019-1125)

For more details about the security issue(s), including the impact, a
CVSS score, acknowledgments, and other related information, refer to
the CVE page(s) listed in the References section.

Bug Fix(es) :

* OOPS with NULL pointer exception in v4l2_ctrl_query_menu when second
arg of function is NULL (BZ#1647975)

* Another RHEL 6 hang in congestion_wait() (BZ#1658254)

* kernel crash after running user space script (BZ#1663262)

* RHEL-6.10: Don't report the use of retpoline on Skylake as
vulnerable (BZ# 1666102)

* Bad pagetable: 000f '*pdpt = 0000000000000000 *pde =
0000000000000000' RHEL 6 32bit (BZ#1702782)

* fs/binfmt_misc.c: do not allow offset overflow [6.10.z] (BZ#1710149)

* Wrong spectre backport causing linux headers to break compilation of
3rd party packages (BZ#1722185)"
  );
  # https://lists.centos.org/pipermail/centos-announce/2019-August/023404.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?2ebba086"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected kernel packages."
  );
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2017-17805");
  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:kernel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:kernel-abi-whitelists");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:kernel-debug");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:kernel-debug-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:kernel-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:kernel-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:kernel-firmware");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:kernel-headers");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:perf");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:python-perf");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:centos:centos:6");

  script_set_attribute(attribute:"vuln_publication_date", value:"2017/12/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/08/16");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/08/20");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2019-2020 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);
release = get_kb_item("Host/CentOS/release");
if (isnull(release) || "CentOS" >!< release) audit(AUDIT_OS_NOT, "CentOS");
os_ver = pregmatch(pattern: "CentOS(?: Linux)? release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "CentOS");
os_ver = os_ver[1];
if (! preg(pattern:"^6([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "CentOS 6.x", "CentOS " + os_ver);

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:"kernel-2.6.32-754.18.2.el6")) flag++;
if (rpm_check(release:"CentOS-6", reference:"kernel-abi-whitelists-2.6.32-754.18.2.el6")) flag++;
if (rpm_check(release:"CentOS-6", reference:"kernel-debug-2.6.32-754.18.2.el6")) flag++;
if (rpm_check(release:"CentOS-6", reference:"kernel-debug-devel-2.6.32-754.18.2.el6")) flag++;
if (rpm_check(release:"CentOS-6", reference:"kernel-devel-2.6.32-754.18.2.el6")) flag++;
if (rpm_check(release:"CentOS-6", reference:"kernel-doc-2.6.32-754.18.2.el6")) flag++;
if (rpm_check(release:"CentOS-6", reference:"kernel-firmware-2.6.32-754.18.2.el6")) flag++;
if (rpm_check(release:"CentOS-6", reference:"kernel-headers-2.6.32-754.18.2.el6")) flag++;
if (rpm_check(release:"CentOS-6", reference:"perf-2.6.32-754.18.2.el6")) flag++;
if (rpm_check(release:"CentOS-6", reference:"python-perf-2.6.32-754.18.2.el6")) flag++;


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