Oracle Linux 6 : microcode_ctl (ELSA-2018-0013) (Spectre)

2018-01-05T00:00:00
ID ORACLELINUX_ELSA-2018-0013.NASL
Type nessus
Reporter Tenable
Modified 2018-07-24T00:00:00

Description

From Red Hat Security Advisory 2018:0013 :

An update for microcode_ctl 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 microcode_ctl packages provide microcode updates for Intel and AMD processors.

Security Fix(es) :

  • An industry-wide issue was found in the way many modern microprocessor designs have implemented speculative execution of instructions (a commonly used performance optimization). There are three primary variants of the issue which differ in the way the speculative execution can be exploited. Variant CVE-2017-5715 triggers the speculative execution by utilizing branch target injection. It relies on the presence of a precisely-defined instruction sequence in the privileged code as well as the fact that memory accesses may cause allocation 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 cross the syscall and guest/host boundaries and read privileged memory by conducting targeted cache side-channel attacks. (CVE-2017-5715)

Note: This is the microcode counterpart of the CVE-2017-5715 kernel mitigation.

Red Hat would like to thank Google Project Zero for reporting this issue.

                                        
                                            #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Red Hat Security Advisory RHSA-2018:0013 and 
# Oracle Linux Security Advisory ELSA-2018-0013 respectively.
#

include("compat.inc");

if (description)
{
  script_id(105601);
  script_version("3.6");
  script_cvs_date("Date: 2018/07/24 18:56:13");

  script_cve_id("CVE-2017-5715");
  script_xref(name:"RHSA", value:"2018:0013");
  script_xref(name:"IAVA", value:"2018-A-0020");

  script_name(english:"Oracle Linux 6 : microcode_ctl (ELSA-2018-0013) (Spectre)");
  script_summary(english:"Checks rpm output for the updated package");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Oracle Linux host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"From Red Hat Security Advisory 2018:0013 :

An update for microcode_ctl 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 microcode_ctl packages provide microcode updates for Intel and AMD
processors.

Security Fix(es) :

* An industry-wide issue was found in the way many modern
microprocessor designs have implemented speculative execution of
instructions (a commonly used performance optimization). There are
three primary variants of the issue which differ in the way the
speculative execution can be exploited. Variant CVE-2017-5715 triggers
the speculative execution by utilizing branch target injection. It
relies on the presence of a precisely-defined instruction sequence in
the privileged code as well as the fact that memory accesses may cause
allocation 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 cross the
syscall and guest/host boundaries and read privileged memory by
conducting targeted cache side-channel attacks. (CVE-2017-5715)

Note: This is the microcode counterpart of the CVE-2017-5715 kernel
mitigation.

Red Hat would like to thank Google Project Zero for reporting this
issue."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://oss.oracle.com/pipermail/el-errata/2018-January/007435.html"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected microcode_ctl package."
  );
  script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/C:C/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:H/PR:L/UI:N/S:C/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:oracle:linux:microcode_ctl");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:oracle:linux:6");

  script_set_attribute(attribute:"patch_publication_date", value:"2018/01/04");
  script_set_attribute(attribute:"in_the_news", value:"true");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/01/05");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2018 Tenable Network Security, Inc.");
  script_family(english:"Oracle Linux Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/OracleLinux", "Host/RedHat/release", "Host/RedHat/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/OracleLinux")) audit(AUDIT_OS_NOT, "Oracle Linux");
release = get_kb_item("Host/RedHat/release");
if (isnull(release) || !eregmatch(pattern: "Oracle (?:Linux Server|Enterprise Linux)", string:release)) audit(AUDIT_OS_NOT, "Oracle Linux");
os_ver = eregmatch(pattern: "Oracle (?:Linux Server|Enterprise Linux) .*release ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Oracle Linux");
os_ver = os_ver[1];
if (! ereg(pattern:"^6([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Oracle Linux 6", "Oracle Linux " + 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$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Oracle Linux", cpu);

flag = 0;
if (rpm_check(release:"EL6", reference:"microcode_ctl-1.17-25.2.el6_9")) flag++;


if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:rpm_report_get());
  else security_warning(0);
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "microcode_ctl");
}