Ubuntu 20.04 LTS : Python vulnerability (USN-4973-2)

#%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-4973-2. 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(153852);
  script_version("1.5");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/10/23");

  script_cve_id("CVE-2021-29921");
  script_xref(name:"USN", value:"4973-2");
  script_xref(name:"IAVA", value:"2021-A-0263-S");

  script_name(english:"Ubuntu 20.04 LTS : Python vulnerability (USN-4973-2)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The remote Ubuntu 20.04 LTS host has packages installed that are affected by a vulnerability as referenced in the
USN-4973-2 advisory.

  - In Python before 3,9,5, the ipaddress library mishandles leading zero characters in the octets of an IP
    address string. This (in some situations) allows attackers to bypass access control that is based on IP
    addresses. (CVE-2021-29921)

Note that Nessus has not tested for this issue 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-4973-2");
  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:F/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:F/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-29921");

  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:"2021/05/06");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/10/04");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/10/04");

  script_set_attribute(attribute:"plugin_type", value:"local");
  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:idle-python3.8");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpython3.8");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpython3.8-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpython3.8-minimal");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpython3.8-stdlib");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpython3.8-testsuite");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3.8");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3.8-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3.8-examples");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3.8-full");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3.8-minimal");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3.8-venv");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"Ubuntu Security Notice (C) 2021-2023 Canonical, Inc. / NASL script (C) 2021-2023 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 (! ('20.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 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': '20.04', 'pkgname': 'idle-python3.8', 'pkgver': '3.8.10-0ubuntu1~20.04.1'},
    {'osver': '20.04', 'pkgname': 'libpython3.8', 'pkgver': '3.8.10-0ubuntu1~20.04.1'},
    {'osver': '20.04', 'pkgname': 'libpython3.8-dev', 'pkgver': '3.8.10-0ubuntu1~20.04.1'},
    {'osver': '20.04', 'pkgname': 'libpython3.8-minimal', 'pkgver': '3.8.10-0ubuntu1~20.04.1'},
    {'osver': '20.04', 'pkgname': 'libpython3.8-stdlib', 'pkgver': '3.8.10-0ubuntu1~20.04.1'},
    {'osver': '20.04', 'pkgname': 'libpython3.8-testsuite', 'pkgver': '3.8.10-0ubuntu1~20.04.1'},
    {'osver': '20.04', 'pkgname': 'python3.8', 'pkgver': '3.8.10-0ubuntu1~20.04.1'},
    {'osver': '20.04', 'pkgname': 'python3.8-dev', 'pkgver': '3.8.10-0ubuntu1~20.04.1'},
    {'osver': '20.04', 'pkgname': 'python3.8-examples', 'pkgver': '3.8.10-0ubuntu1~20.04.1'},
    {'osver': '20.04', 'pkgname': 'python3.8-full', 'pkgver': '3.8.10-0ubuntu1~20.04.1'},
    {'osver': '20.04', 'pkgname': 'python3.8-minimal', 'pkgver': '3.8.10-0ubuntu1~20.04.1'},
    {'osver': '20.04', 'pkgname': 'python3.8-venv', 'pkgver': '3.8.10-0ubuntu1~20.04.1'}
];

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, 'idle-python3.8 / libpython3.8 / libpython3.8-dev / etc');
}