Ubuntu 14.04 LTS : PAM vulnerabilities (USN-2935-1)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-2935-1. 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(89996);
  script_version("2.11");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/10/20");

  script_cve_id("CVE-2013-7041", "CVE-2014-2583", "CVE-2015-3238");
  script_xref(name:"USN", value:"2935-1");

  script_name(english:"Ubuntu 14.04 LTS : PAM vulnerabilities (USN-2935-1)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"It was discovered that the PAM pam_userdb module incorrectly used a
case-insensitive method when comparing hashed passwords. A local
attacker could possibly use this issue to make brute-force attacks
easier. This issue only affected Ubuntu 12.04 LTS and Ubuntu 14.04
LTS. (CVE-2013-7041)

Sebastian Krahmer discovered that the PAM pam_timestamp module
incorrectly performed filtering. A local attacker could use this issue
to create arbitrary files, or possibly bypass authentication. This
issue only affected Ubuntu 12.04 LTS and Ubuntu 14.04 LTS.
(CVE-2014-2583)

Sebastien Macke discovered that the PAM pam_unix module incorrectly
handled large passwords. A local attacker could possibly use this
issue in certain environments to enumerate usernames or cause a denial
of service. (CVE-2015-3238).

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://ubuntu.com/security/notices/USN-2935-1");
  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:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2015-3238");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2014/04/10");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/03/16");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/03/17");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpam-modules");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpam-modules-bin");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpam-runtime");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpam0g");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpam0g-dev");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpam-cracklib");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Ubuntu Local Security Checks");

  script_copyright(english:"Ubuntu Security Notice (C) 2016-2023 Canonical, Inc. / NASL script (C) 2016-2023 and is owned by Tenable, Inc. or an Affiliate thereof.");

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

  exit(0);
}

include('debian_package.inc');

if ( ! get_kb_item('Host/local_checks_enabled') ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_release = get_kb_item('Host/Ubuntu/release');
if ( isnull(os_release) ) audit(AUDIT_OS_NOT, 'Ubuntu');
os_release = chomp(os_release);
if (! ('14.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 14.04', 'Ubuntu ' + os_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);

var pkgs = [
    {'osver': '14.04', 'pkgname': 'libpam-cracklib', 'pkgver': '1.1.8-1ubuntu2.1'},
    {'osver': '14.04', 'pkgname': 'libpam-modules', 'pkgver': '1.1.8-1ubuntu2.1'},
    {'osver': '14.04', 'pkgname': 'libpam-modules-bin', 'pkgver': '1.1.8-1ubuntu2.1'},
    {'osver': '14.04', 'pkgname': 'libpam-runtime', 'pkgver': '1.1.8-1ubuntu2.1'},
    {'osver': '14.04', 'pkgname': 'libpam0g', 'pkgver': '1.1.8-1ubuntu2.1'},
    {'osver': '14.04', 'pkgname': 'libpam0g-dev', 'pkgver': '1.1.8-1ubuntu2.1'}
];

var flag = 0;
foreach package_array ( pkgs ) {
  var osver = NULL;
  var pkgname = NULL;
  var pkgver = NULL;
  if (!empty_or_null(package_array['osver'])) osver = package_array['osver'];
  if (!empty_or_null(package_array['pkgname'])) pkgname = package_array['pkgname'];
  if (!empty_or_null(package_array['pkgver'])) pkgver = package_array['pkgver'];
  if (osver && pkgname && pkgver) {
    if (ubuntu_check(osver:osver, pkgname:pkgname, pkgver:pkgver)) flag++;
  }
}

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    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, 'libpam-cracklib / libpam-modules / libpam-modules-bin / etc');
}