Ubuntu 11.04 / 11.10 : isc-dhcp vulnerability (USN-1309-1)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-1309-1. 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(57321);
  script_version("1.9");
  script_cvs_date("Date: 2019/09/19 12:54:27");

  script_cve_id("CVE-2011-4539");
  script_xref(name:"USN", value:"1309-1");

  script_name(english:"Ubuntu 11.04 / 11.10 : isc-dhcp vulnerability (USN-1309-1)");
  script_summary(english:"Checks dpkg output for updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Ubuntu host is missing a security-related patch."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"It was discovered that the DHCP server incorrectly handled certain
malformed packets when configured to evaluate regular expressions. A
remote attacker could use this issue to cause DHCP to crash, 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:"see_also",
    value:"https://usn.ubuntu.com/1309-1/"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected isc-dhcp-server package."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:isc-dhcp-server");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:11.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:11.10");

  script_set_attribute(attribute:"vuln_publication_date", value:"2011/12/08");
  script_set_attribute(attribute:"patch_publication_date", value:"2011/12/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2011/12/16");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2011-2019 Canonical, Inc. / NASL script (C) 2011-2019 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 (! preg(pattern:"^(11\.04|11\.10)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 11.04 / 11.10", "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:"11.04", pkgname:"isc-dhcp-server", pkgver:"4.1.1-P1-15ubuntu9.3")) flag++;
if (ubuntu_check(osver:"11.10", pkgname:"isc-dhcp-server", pkgver:"4.1.1-P1-17ubuntu10.1")) 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, "isc-dhcp-server");
}