RHEL 7 : kernel (RHSA-2018:2790)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Red Hat Security Advisory RHSA-2018:2790. The text 
# itself is copyright (C) Red Hat, Inc.
#

include('compat.inc');

if (description)
{
  script_id(117782);
  script_version("1.9");
  script_set_attribute(attribute:"plugin_modification_date", value:"2022/02/25");

  script_cve_id("CVE-2018-5390");
  script_xref(name:"RHSA", value:"2018:2790");

  script_name(english:"RHEL 7 : kernel (RHSA-2018:2790)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Red Hat 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 7.2
Advanced Update Support, Red Hat Enterprise Linux 7.2 Telco Extended
Update Support, and Red Hat Enterprise Linux 7.2 Update Services for
SAP Solutions.

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) :

* A flaw named SegmentSmack was found in the way the Linux kernel
handled specially crafted TCP packets. A remote attacker could use
this flaw to trigger time and calculation expensive calls to
tcp_collapse_ofo_queue() and tcp_prune_ofo_queue() functions by
sending specially modified packets within ongoing TCP sessions which
could lead to a CPU saturation and hence a denial of service on the
system. Maintaining the denial of service condition requires
continuous two-way TCP sessions to a reachable open port, thus the
attacks cannot be performed using spoofed IP addresses.
(CVE-2018-5390)

Red Hat would like to thank Juha-Matti Tilli (Aalto University -
Department of Communications and Networking and Nokia Bell Labs) for
reporting this issue.

Bug Fix(es) :

* Previously, the early microcode updater in the kernel was trying to
perform a microcode update on virtualized guests. As a consequence,
the virtualized guests sometimes mishandled the request to perform the
microcode update and became unresponsive in the early boot stage. This
update applies an upstream patch to avoid the early microcode update
when running under a hypervisor. As a result, no kernel freezes appear
in the described scenario. (BZ#1618386)");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/errata/RHSA-2018:2790");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/security/cve/cve-2018-5390");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C");
  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:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2018-5390");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/08/06");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/09/25");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/09/27");

  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-abi-whitelists");
  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-headers");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-tools-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-tools-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-tools-libs-devel");
  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:7.2");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Red Hat Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2018-2022 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl", "linux_alt_patch_detect.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");
include("ksplice.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 = pregmatch(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 (! preg(pattern:"^7\.2([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Red Hat 7.2", "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);

if (get_one_kb_item("Host/ksplice/kernel-cves"))
{
  rm_kb_item(name:"Host/uptrack-uname-r");
  cve_list = make_list("CVE-2018-5390");
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, "KSplice hotfix for RHSA-2018:2790");
  }
  else
  {
    __rpm_report = ksplice_reporting_text();
  }
}

yum_updateinfo = get_kb_item("Host/RedHat/yum-updateinfo");
if (!empty_or_null(yum_updateinfo)) 
{
  rhsa = "RHSA-2018:2790";
  yum_report = redhat_generate_yum_updateinfo_report(rhsa:rhsa);
  if (!empty_or_null(yum_report))
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      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:"RHEL7", sp:"2", cpu:"x86_64", reference:"kernel-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", reference:"kernel-abi-whitelists-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"kernel-debug-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"kernel-debug-debuginfo-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"kernel-debug-devel-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"kernel-debuginfo-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"kernel-debuginfo-common-x86_64-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"kernel-devel-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", reference:"kernel-doc-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"kernel-headers-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"kernel-tools-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"kernel-tools-debuginfo-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"kernel-tools-libs-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"kernel-tools-libs-devel-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"perf-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"perf-debuginfo-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"python-perf-3.10.0-327.73.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"2", cpu:"x86_64", reference:"python-perf-debuginfo-3.10.0-327.73.1.el7")) flag++;

  if (flag)
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      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-abi-whitelists / kernel-debug / etc");
  }
}