Ubuntu 12.04 LTS / 14.04 LTS / 15.10 : libtasn1-3, libtasn1-6 vulnerability (USN-2957-1)

2016-05-03T00:00:00
ID UBUNTU_USN-2957-1.NASL
Type nessus
Reporter Tenable
Modified 2018-08-03T00:00:00

Description

Pascal Cuoq and Miod Vallat discovered that Libtasn1 incorrectly handled certain malformed DER certificates. A remote attacker could possibly use this issue to cause applications using Libtasn1 to hang, resulting in 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-2957-1. 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(90856);
  script_version("2.6");
  script_cvs_date("Date: 2018/08/03 12:21:25");

  script_cve_id("CVE-2016-4008");
  script_xref(name:"USN", value:"2957-1");

  script_name(english:"Ubuntu 12.04 LTS / 14.04 LTS / 15.10 : libtasn1-3, libtasn1-6 vulnerability (USN-2957-1)");
  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:
"Pascal Cuoq and Miod Vallat discovered that Libtasn1 incorrectly
handled certain malformed DER certificates. A remote attacker could
possibly use this issue to cause applications using Libtasn1 to hang,
resulting in 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:"solution", 
    value:"Update the affected libtasn1-3 and / or libtasn1-6 packages."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:N/I:N/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:H/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:"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:libtasn1-3");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libtasn1-6");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:12.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:15.10");

  script_set_attribute(attribute:"patch_publication_date", value:"2016/05/02");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/05/03");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2016-2018 Canonical, Inc. / NASL script (C) 2016 Tenable Network Security, Inc.");
  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:"^(12\.04|14\.04|15\.10)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 12.04 / 14.04 / 15.10", "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:"12.04", pkgname:"libtasn1-3", pkgver:"2.10-1ubuntu1.5")) flag++;
if (ubuntu_check(osver:"14.04", pkgname:"libtasn1-6", pkgver:"3.4-3ubuntu0.4")) flag++;
if (ubuntu_check(osver:"15.10", pkgname:"libtasn1-6", pkgver:"4.5-2ubuntu0.1")) 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, "libtasn1-3 / libtasn1-6");
}