Ubuntu 16.04 LTS / 18.04 LTS / 20.04 : ppp vulnerability (USN-4451-1)

2020-08-06T00:00:00
ID UBUNTU_USN-4451-1.NASL
Type nessus
Reporter Ubuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
Modified 2020-08-06T00:00:00

Description

Thomas Chauchefoin working with Trend Micro's Zero Day Initiative, discovered that ppp incorrectly handled module loading. A local attacker could use this issue to load arbitrary kernel modules and possibly execute arbitrary code.

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-4451-1. 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(139371);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/09/17");

  script_cve_id("CVE-2020-15704");
  script_xref(name:"USN", value:"4451-1");

  script_name(english:"Ubuntu 16.04 LTS / 18.04 LTS / 20.04 : ppp vulnerability (USN-4451-1)");
  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:
"Thomas Chauchefoin working with Trend Micro's Zero Day Initiative,
discovered that ppp incorrectly handled module loading. A local
attacker could use this issue to load arbitrary kernel modules and
possibly execute arbitrary code.

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/4451-1/"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected ppp package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:N");
  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:U/C:H/I:N/A:N");
  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:ppp");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/09/01");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/08/04");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/08/06");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 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:"^(16\.04|18\.04|20\.04)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 16.04 / 18.04 / 20.04", "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:"16.04", pkgname:"ppp", pkgver:"2.4.7-1+2ubuntu1.16.04.3")) flag++;
if (ubuntu_check(osver:"18.04", pkgname:"ppp", pkgver:"2.4.7-2+2ubuntu1.3")) flag++;
if (ubuntu_check(osver:"20.04", pkgname:"ppp", pkgver:"2.4.7-2+4.1ubuntu5.1")) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_NOTE,
    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, "ppp");
}