Ubuntu 14.04 LTS / 16.04 LTS : Zsh vulnerabilities (USN-3593-1)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-3593-1. 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(107257);
  script_version("1.7");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/10/23");

  script_cve_id(
    "CVE-2014-10070",
    "CVE-2014-10071",
    "CVE-2014-10072",
    "CVE-2016-10714",
    "CVE-2017-18205",
    "CVE-2017-18206",
    "CVE-2018-7548",
    "CVE-2018-7549"
  );
  script_xref(name:"USN", value:"3593-1");

  script_name(english:"Ubuntu 14.04 LTS / 16.04 LTS : Zsh vulnerabilities (USN-3593-1)");

  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 Zsh incorrectly handled certain enviroment
variables. An attacker could possibly use this issue to gain
privileged access to the system. This issue only affected Ubuntu 14.04
LTS. (CVE-2014-10070)

It was discovered that Zsh incorrectly handled certain inputs. An
attacker could possibly use this to execute arbitrary code. This issue
only affected Ubuntu 14.04 LTS. (CVE-2014-10071)

It was discovered that Zsh incorrectly handled some symbolic links. An
attacker could possibly use this to execute arbitrary code. This issue
only affected Ubuntu 14.04 LTS. (CVE-2014-10072)

It was discovered that Zsh incorrectly handled certain errors. An
attacker could possibly use this issue to cause a denial of service.
(CVE-2016-10714)

It was discovered that Zsh incorrectly handled certain commands. An
attacker could possibly use this to execute arbitrary code.
(CVE-2017-18205)

It was discovered that Zsh incorrectly handled certain symlinks. An
attacker could possibly use this to execute arbitrary code. This issue
only affected Ubuntu 16.04 LTS and Ubuntu 17.10. (CVE-2017-18206)

It was discovered that Zsh incorrectly handled certain inputs. An
attacker could possible use to execute arbitrary code. This issue only
affected Ubuntu 17.10. (CVE-2018-7548)

It was discovered that Zsh incorrectly handled certain inputs. An
attacker could possibly use this to cause a denial of service.
(CVE-2018-7549).

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-3593-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/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:N/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:"cvss_score_source", value:"CVE-2018-7548");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/02/27");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/03/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/03/09");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:zsh");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:zsh-beta");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:zsh-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:zsh-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:zsh-static");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:lts");
  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) 2018-2023 Canonical, Inc. / NASL script (C) 2018-2023 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 || '16.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 14.04 / 16.04', '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': 'zsh', 'pkgver': '5.0.2-3ubuntu6.1'},
    {'osver': '14.04', 'pkgname': 'zsh-beta', 'pkgver': '5.0.2-3ubuntu6.1'},
    {'osver': '14.04', 'pkgname': 'zsh-common', 'pkgver': '5.0.2-3ubuntu6.1'},
    {'osver': '14.04', 'pkgname': 'zsh-dev', 'pkgver': '5.0.2-3ubuntu6.1'},
    {'osver': '14.04', 'pkgname': 'zsh-static', 'pkgver': '5.0.2-3ubuntu6.1'},
    {'osver': '16.04', 'pkgname': 'zsh', 'pkgver': '5.1.1-1ubuntu2.1'},
    {'osver': '16.04', 'pkgname': 'zsh-common', 'pkgver': '5.1.1-1ubuntu2.1'},
    {'osver': '16.04', 'pkgname': 'zsh-dev', 'pkgver': '5.1.1-1ubuntu2.1'},
    {'osver': '16.04', 'pkgname': 'zsh-static', 'pkgver': '5.1.1-1ubuntu2.1'}
];

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_HOLE,
    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, 'zsh / zsh-beta / zsh-common / zsh-dev / zsh-static');
}