RHEL 7 : kernel (RHSA-2018:2161) (Spectre)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Red Hat Security Advisory RHSA-2018:2161. The text 
# itself is copyright (C) Red Hat, Inc.
#

include("compat.inc");

if (description)
{
  script_id(110999);
  script_version("1.10");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/04/15");

  script_cve_id("CVE-2018-3639");
  script_xref(name:"RHSA", value:"2018:2161");

  script_name(english:"RHEL 7 : kernel (RHSA-2018:2161) (Spectre)");
  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:
"An update for kernel is now available for Red Hat Enterprise Linux 7.3
Extended Update Support.

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) :

* An industry-wide issue was found in the way many modern
microprocessor designs have implemented speculative execution of Load
& Store instructions (a commonly used performance optimization). It
relies on the presence of a precisely-defined instruction sequence in
the privileged code as well as the fact that memory read from address
to which a recent memory write has occurred may see an older value and
subsequently cause an update into the microprocessor's data cache even
for speculatively executed instructions that never actually commit
(retire). As a result, an unprivileged attacker could use this flaw to
read privileged memory by conducting targeted cache side-channel
attacks. (CVE-2018-3639, x86 AMD)

Red Hat would like to thank Ken Johnson (Microsoft Security Response
Center) and Jann Horn (Google Project Zero) for reporting this issue.

Bug Fix(es) :

* When a Nonvolatile Memory Express (NVMe) namespace was created,
changed, or deleted, an occasional deadlock occurred. With this
update, namespace scanning and removal does not hold a mutual
exclusion (mutex) program object. As a result, a deadlock no longer
occurs in the described scenario. (BZ#1566886)

* Previously, a live migration of a virtual machine from one host with
updated firmware to another host without updated firmware resulted in
incorrect kernel settings for Meltdown mitigations, which could leave
the kernel vulnerable to Meltdown. With this fix, the firmware on the
new physical host is re-scanned for updates after a live migration. As
a result, the kernel uses the correct mitigation in the described
scenario. (BZ#1570507)

* Previously, microcode updates on 32 and 64-bit AMD and Intel
architectures were not synchronized. As a consequence, it was not
possible to apply the microcode updates. This fix adds the
synchronization to the microcode updates so that processors of the
stated architectures receive updates at the same time. As a result,
microcode updates are now synchronized. (BZ# 1578044)

* When switching from the indirect branch speculation (IBRS) feature
to the retpolines feature, the IBRS state of some CPUs was sometimes
not handled correctly. Consequently, some CPUs were left with the IBRS
Model-Specific Register (MSR) bit set to 1, which could lead to
performance issues. With this update, the underlying source code has
been fixed to clear the IBRS MSR bits correctly, thus fixing the bug.
(BZ#1586146)

Users of kernel are advised to upgrade to these updated packages,
which fix these bugs.

The system must be rebooted for this update to take effect."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/errata/RHSA-2018:2161"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/security/cve/cve-2018-3639"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:N");
  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:N/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  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: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-s390x");
  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-kdump");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-kdump-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-kdump-devel");
  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:7.3");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/05/22");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/07/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/07/11");
  script_set_attribute(attribute:"in_the_news", value:"true");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2018-2021 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Red Hat Local Security Checks");

  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\.3([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Red Hat 7.3", "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-2018-3639");
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, "KSplice hotfix for RHSA-2018:2161");
  }
  else
  {
    __rpm_report = ksplice_reporting_text();
  }
}

yum_updateinfo = get_kb_item("Host/RedHat/yum-updateinfo");
if (!empty_or_null(yum_updateinfo)) 
{
  rhsa = "RHSA-2018:2161";
  yum_report = redhat_generate_yum_updateinfo_report(rhsa:rhsa);
  if (!empty_or_null(yum_report))
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_NOTE,
      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:"3", cpu:"s390x", reference:"kernel-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"kernel-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", reference:"kernel-abi-whitelists-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"kernel-debug-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"kernel-debug-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"kernel-debug-debuginfo-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"kernel-debug-debuginfo-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"kernel-debug-devel-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"kernel-debug-devel-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"kernel-debuginfo-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"kernel-debuginfo-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"kernel-debuginfo-common-s390x-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"kernel-debuginfo-common-x86_64-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"kernel-devel-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"kernel-devel-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", reference:"kernel-doc-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"kernel-headers-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"kernel-headers-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"kernel-kdump-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"kernel-kdump-debuginfo-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"kernel-kdump-devel-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"kernel-tools-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"kernel-tools-debuginfo-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"kernel-tools-libs-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"kernel-tools-libs-devel-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"perf-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"perf-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"perf-debuginfo-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"perf-debuginfo-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"python-perf-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"python-perf-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"s390x", reference:"python-perf-debuginfo-3.10.0-514.53.1.el7")) flag++;
  if (rpm_check(release:"RHEL7", sp:"3", cpu:"x86_64", reference:"python-perf-debuginfo-3.10.0-514.53.1.el7")) flag++;

  if (flag)
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_NOTE,
      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");
  }
}