Ubuntu 18.10 : linux-azure vulnerabilities (USN-3878-2)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-3878-2. The text 
# itself is copyright (C) Canonical, Inc. See 
# <http://www.ubuntu.com/usn/>. Ubuntu(R) is a registered 
# trademark of Canonical, Inc.
#

include("compat.inc");

if (description)
{
  script_id(122053);
  script_version("1.7");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/05/11");

  script_cve_id("CVE-2018-14625", "CVE-2018-16882", "CVE-2018-19407", "CVE-2018-19854");
  script_xref(name:"USN", value:"3878-2");

  script_name(english:"Ubuntu 18.10 : linux-azure vulnerabilities (USN-3878-2)");
  script_summary(english:"Checks dpkg output for updated packages.");

  script_set_attribute(
    attribute:"synopsis",
    value:
"The remote Ubuntu host is missing one or more security-related
patches."
  );
  script_set_attribute(
    attribute:"description",
    value:
"It was discovered that a race condition existed in the vsock address
family implementation of the Linux kernel that could lead to a
use-after-free condition. A local attacker in a guest virtual machine
could use this to expose sensitive information (host machine kernel
memory). (CVE-2018-14625)

Cfir Cohen discovered that a use-after-free vulnerability existed in
the KVM implementation of the Linux kernel, when handling interrupts
in environments where nested virtualization is in use (nested KVM
virtualization is not enabled by default in Ubuntu kernels). A local
attacker in a guest VM could possibly use this to gain administrative
privileges in a host machine. (CVE-2018-16882)

Wei Wu discovered that the KVM implementation in the Linux kernel did
not properly ensure that ioapics were initialized. A local attacker
could use this to cause a denial of service (system crash).
(CVE-2018-19407)

It was discovered that the crypto subsystem of the Linux kernel leaked
uninitialized memory to user space in some situations. A local
attacker could use this to expose sensitive information (kernel
memory). (CVE-2018-19854).

Note that Tenable Network Security has extracted the preceding
description block directly from the Ubuntu security advisory. Tenable
has attempted to automatically clean and format it as much as possible
without introducing additional issues."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://usn.ubuntu.com/3878-2/"
  );
  script_set_attribute(
    attribute:"solution",
    value:
"Update the affected linux-image-4.18-azure and / or linux-image-azure
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:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.18-azure");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-azure");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.10");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/09/10");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/02/07");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/02/08");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2019-2023 Canonical, Inc. / NASL script (C) 2019-2023 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Ubuntu Local Security Checks");

  script_dependencies("ssh_get_info.nasl", "linux_alt_patch_detect.nasl");
  script_require_keys("Host/cpu", "Host/Ubuntu", "Host/Ubuntu/release", "Host/Debian/dpkg-l");

  exit(0);
}


include("audit.inc");
include("ubuntu.inc");
include("ksplice.inc");

if ( ! get_kb_item("Host/local_checks_enabled") ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var release = get_kb_item("Host/Ubuntu/release");
if ( isnull(release) ) audit(AUDIT_OS_NOT, "Ubuntu");
release = chomp(release);
if (! preg(pattern:"^(18\.10)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 18.10", "Ubuntu " + release);
if ( ! get_kb_item("Host/Debian/dpkg-l") ) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 's390' >!< cpu && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Ubuntu', cpu);

if (get_one_kb_item("Host/ksplice/kernel-cves"))
{
  rm_kb_item(name:"Host/uptrack-uname-r");
  cve_list = make_list("CVE-2018-14625", "CVE-2018-16882", "CVE-2018-19407", "CVE-2018-19854");
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, "KSplice hotfix for USN-3878-2");
  }
  else
  {
    _ubuntu_report = ksplice_reporting_text();
  }
}

var flag = 0;

if (ubuntu_check(osver:"18.10", pkgname:"linux-image-4.18.0-1008-azure", pkgver:"4.18.0-1008.8")) flag++;
if (ubuntu_check(osver:"18.10", pkgname:"linux-image-azure", pkgver:"4.18.0.1008.9")) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : ubuntu_report_get()
  );
  exit(0);
}
else
{
  var tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "linux-image-4.18-azure / linux-image-azure");
}