Ubuntu 18.04 LTS / 20.04 LTS : strongSwan vulnerabilities (USN-5111-1)

##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-5111-1. The text
# itself is copyright (C) Canonical, Inc. See
# <https://ubuntu.com/security/notices>. Ubuntu(R) is a registered
# trademark of Canonical, Inc.
##

include('compat.inc');

if (description)
{
  script_id(154227);
  script_version("1.7");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/10/16");

  script_cve_id("CVE-2021-41990", "CVE-2021-41991");
  script_xref(name:"USN", value:"5111-1");

  script_name(english:"Ubuntu 18.04 LTS / 20.04 LTS : strongSwan vulnerabilities (USN-5111-1)");

  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 / 21.04 / 21.10 host has packages installed that are affected by multiple
vulnerabilities as referenced in the USN-5111-1 advisory.

  - The gmp plugin in strongSwan before 5.9.4 has a remote integer overflow via a crafted certificate with an
    RSASSA-PSS signature. For example, this can be triggered by an unrelated self-signed CA certificate sent
    by an initiator. Remote code execution cannot occur. (CVE-2021-41990)

  - The in-memory certificate cache in strongSwan before 5.9.4 has a remote integer overflow upon receiving
    many requests with different certificates to fill the cache and later trigger the replacement of cache
    entries. The code attempts to select a less-often-used cache entry by means of a random number generator,
    but this is not done correctly. Remote code execution might be a slight possibility. (CVE-2021-41991)

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-5111-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/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:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-41991");

  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:"2021/10/18");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/10/19");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/10/19");

  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:charon-cmd");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:charon-systemd");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libcharon-extauth-plugins");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libcharon-extra-plugins");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libcharon-standard-plugins");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libstrongswan");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libstrongswan-extra-plugins");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libstrongswan-standard-plugins");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:strongswan");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:strongswan-charon");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:strongswan-libcharon");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:strongswan-nm");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:strongswan-pki");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:strongswan-scepclient");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:strongswan-starter");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:strongswan-swanctl");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:strongswan-tnc-base");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:strongswan-tnc-client");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:strongswan-tnc-ifmap");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:strongswan-tnc-pdp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:strongswan-tnc-server");
  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) 2021-2023 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 (! ('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': 'charon-cmd', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'charon-systemd', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'libcharon-extra-plugins', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'libcharon-standard-plugins', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'libstrongswan', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'libstrongswan-extra-plugins', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'libstrongswan-standard-plugins', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'strongswan', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'strongswan-charon', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'strongswan-libcharon', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'strongswan-nm', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'strongswan-pki', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'strongswan-scepclient', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'strongswan-starter', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'strongswan-swanctl', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'strongswan-tnc-base', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'strongswan-tnc-client', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'strongswan-tnc-ifmap', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'strongswan-tnc-pdp', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '18.04', 'pkgname': 'strongswan-tnc-server', 'pkgver': '5.6.2-1ubuntu2.7'},
    {'osver': '20.04', 'pkgname': 'charon-cmd', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'charon-systemd', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'libcharon-extauth-plugins', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'libcharon-extra-plugins', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'libcharon-standard-plugins', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'libstrongswan', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'libstrongswan-extra-plugins', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'libstrongswan-standard-plugins', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'strongswan', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'strongswan-charon', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'strongswan-libcharon', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'strongswan-nm', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'strongswan-pki', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'strongswan-scepclient', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'strongswan-starter', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'strongswan-swanctl', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'strongswan-tnc-base', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'strongswan-tnc-client', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'strongswan-tnc-ifmap', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'strongswan-tnc-pdp', 'pkgver': '5.8.2-1ubuntu3.3'},
    {'osver': '20.04', 'pkgname': 'strongswan-tnc-server', 'pkgver': '5.8.2-1ubuntu3.3'}
];

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, 'charon-cmd / charon-systemd / libcharon-extauth-plugins / etc');
}