Ubuntu 18.04 LTS / 20.04 LTS : BusyBox vulnerabilities (USN-5179-1)

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-5179-1. The text
# itself is copyright (C) Canonical, Inc. See
# <https://ubuntu.com/security/notices>. Ubuntu(R) is a registered
# trademark of Canonical, Inc.
##

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(155939);
  script_version("1.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/09/19");

  script_cve_id(
    "CVE-2021-28831",
    "CVE-2021-42374",
    "CVE-2021-42378",
    "CVE-2021-42379",
    "CVE-2021-42380",
    "CVE-2021-42381",
    "CVE-2021-42382",
    "CVE-2021-42384",
    "CVE-2021-42385",
    "CVE-2021-42386"
  );
  script_xref(name:"USN", value:"5179-1");

  script_name(english:"Ubuntu 18.04 LTS / 20.04 LTS : BusyBox vulnerabilities (USN-5179-1)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Ubuntu 18.04 LTS / 20.04 LTS host has packages installed that are affected by multiple vulnerabilities as
referenced in the USN-5179-1 advisory.

    It was discovered that BusyBox incorrectly handled certain malformed gzip archives. If a user or automated
    system were tricked into processing a specially crafted gzip archive, a remote attacker could use this
    issue to cause BusyBox to crash, resulting in a denial of service, or possibly execute arbitrary code.
    (CVE-2021-28831)

    It was discovered that BusyBox incorrectly handled certain malformed LZMA archives. If a user or automated
    system were tricked into processing a specially crafted LZMA archive, a remote attacker could use this
    issue to cause BusyBox to crash, resulting in a denial of service, or possibly leak sensitive information.
    (CVE-2021-42374)

    Vera Mens, Uri Katz, Tal Keren, Sharon Brizinov, and Shachar Menashe discovered that BusyBox incorrectly
    handled certain awk patterns. If a user or automated system were tricked into processing a specially
    crafted awk pattern, a remote attacker could use this issue to cause BusyBox to crash, resulting in a
    denial of service, or possibly execute arbitrary code. (CVE-2021-42378, CVE-2021-42379, CVE-2021-42380,
    CVE-2021-42381, CVE-2021-42382, CVE-2021-42384, CVE-2021-42385, CVE-2021-42386)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/notices/USN-5179-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:P/I:P/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:H/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:P");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-42386");
  script_set_attribute(attribute:"cvss4_score_source", value:"CVE-2021-28831");

  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:"2021/03/19");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/12/07");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/12/08");

  script_set_attribute(attribute:"plugin_type", value:"local");
  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:-:lts");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:busybox");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:busybox-initramfs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:busybox-static");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:busybox-syslogd");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:udhcpc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:udhcpd");
  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) 2021-2024 Canonical, Inc. / NASL script (C) 2021-2024 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 (! ('18.04' >< os_release || '20.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 18.04 / 20.04', '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': '18.04', 'pkgname': 'busybox', 'pkgver': '1:1.27.2-2ubuntu3.4'},
    {'osver': '18.04', 'pkgname': 'busybox-initramfs', 'pkgver': '1:1.27.2-2ubuntu3.4'},
    {'osver': '18.04', 'pkgname': 'busybox-static', 'pkgver': '1:1.27.2-2ubuntu3.4'},
    {'osver': '18.04', 'pkgname': 'busybox-syslogd', 'pkgver': '1:1.27.2-2ubuntu3.4'},
    {'osver': '18.04', 'pkgname': 'udhcpc', 'pkgver': '1:1.27.2-2ubuntu3.4'},
    {'osver': '18.04', 'pkgname': 'udhcpd', 'pkgver': '1:1.27.2-2ubuntu3.4'},
    {'osver': '20.04', 'pkgname': 'busybox', 'pkgver': '1:1.30.1-4ubuntu6.4'},
    {'osver': '20.04', 'pkgname': 'busybox-initramfs', 'pkgver': '1:1.30.1-4ubuntu6.4'},
    {'osver': '20.04', 'pkgname': 'busybox-static', 'pkgver': '1:1.30.1-4ubuntu6.4'},
    {'osver': '20.04', 'pkgname': 'busybox-syslogd', 'pkgver': '1:1.30.1-4ubuntu6.4'},
    {'osver': '20.04', 'pkgname': 'udhcpc', 'pkgver': '1:1.30.1-4ubuntu6.4'},
    {'osver': '20.04', 'pkgname': 'udhcpd', 'pkgver': '1:1.30.1-4ubuntu6.4'}
];

var flag = 0;
foreach var 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)
{
  var extra = '';
  extra += ubuntu_report_get();
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : extra
  );
  exit(0);
}
else
{
  var tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'busybox / busybox-initramfs / busybox-static / busybox-syslogd / etc');
}