Ubuntu 14.04 LTS / 16.04 LTS / 17.04 / 17.10 : libxml2 vulnerability (USN-3513-1)

2017-12-14T00:00:00
ID UBUNTU_USN-3513-1.NASL
Type nessus
Reporter Tenable
Modified 2018-12-01T00:00:00

Description

It was discovered that libxml2 incorrecty handled certain files. An attacker could use this issue with specially constructed XML data to cause libxml2 to consume resources, leading to a denial of service.

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.

                                        
                                            #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-3513-1. 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(105254);
  script_version("3.8");
  script_cvs_date("Date: 2018/12/01 15:12:41");

  script_cve_id("CVE-2017-15412");
  script_xref(name:"USN", value:"3513-1");

  script_name(english:"Ubuntu 14.04 LTS / 16.04 LTS / 17.04 / 17.10 : libxml2 vulnerability (USN-3513-1)");
  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 libxml2 incorrecty handled certain files. An
attacker could use this issue with specially constructed XML data to
cause libxml2 to consume resources, leading to a denial of service.

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/3513-1/"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P");
  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:R/S:U/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:"exploit_available", value:"false");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libxml2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libxml2-utils");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python-libxml2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3-libxml2");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:17.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:17.10");

  script_set_attribute(attribute:"patch_publication_date", value:"2017/12/13");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/12/14");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2017-2018 Canonical, Inc. / NASL script (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Ubuntu Local Security Checks");

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

  exit(0);
}


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

if ( ! get_kb_item("Host/local_checks_enabled") ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/Ubuntu/release");
if ( isnull(release) ) audit(AUDIT_OS_NOT, "Ubuntu");
release = chomp(release);
if (! ereg(pattern:"^(14\.04|16\.04|17\.04|17\.10)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 14.04 / 16.04 / 17.04 / 17.10", "Ubuntu " + release);
if ( ! get_kb_item("Host/Debian/dpkg-l") ) 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, "Ubuntu", cpu);

flag = 0;

if (ubuntu_check(osver:"14.04", pkgname:"libxml2", pkgver:"2.9.1+dfsg1-3ubuntu4.12")) flag++;
if (ubuntu_check(osver:"14.04", pkgname:"libxml2-utils", pkgver:"2.9.1+dfsg1-3ubuntu4.12")) flag++;
if (ubuntu_check(osver:"14.04", pkgname:"python-libxml2", pkgver:"2.9.1+dfsg1-3ubuntu4.12")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"libxml2", pkgver:"2.9.3+dfsg1-1ubuntu0.5")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"libxml2-utils", pkgver:"2.9.3+dfsg1-1ubuntu0.5")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"python-libxml2", pkgver:"2.9.3+dfsg1-1ubuntu0.5")) flag++;
if (ubuntu_check(osver:"17.04", pkgname:"libxml2", pkgver:"2.9.4+dfsg1-2.2ubuntu0.3")) flag++;
if (ubuntu_check(osver:"17.04", pkgname:"libxml2-utils", pkgver:"2.9.4+dfsg1-2.2ubuntu0.3")) flag++;
if (ubuntu_check(osver:"17.04", pkgname:"python-libxml2", pkgver:"2.9.4+dfsg1-2.2ubuntu0.3")) flag++;
if (ubuntu_check(osver:"17.04", pkgname:"python3-libxml2", pkgver:"2.9.4+dfsg1-2.2ubuntu0.3")) flag++;
if (ubuntu_check(osver:"17.10", pkgname:"libxml2", pkgver:"2.9.4+dfsg1-4ubuntu1.2")) flag++;
if (ubuntu_check(osver:"17.10", pkgname:"libxml2-utils", pkgver:"2.9.4+dfsg1-4ubuntu1.2")) flag++;
if (ubuntu_check(osver:"17.10", pkgname:"python-libxml2", pkgver:"2.9.4+dfsg1-4ubuntu1.2")) flag++;
if (ubuntu_check(osver:"17.10", pkgname:"python3-libxml2", pkgver:"2.9.4+dfsg1-4ubuntu1.2")) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : ubuntu_report_get()
  );
  exit(0);
}
else
{
  tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "libxml2 / libxml2-utils / python-libxml2 / python3-libxml2");
}