Ubuntu 16.04 ESM / 18.04 ESM / 20.04 ESM / 22.04 ESM : xrdp vulnerabilities (USN-6474-1)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-6474-1. 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(185416);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/08/27");

  script_cve_id(
    "CVE-2022-23468",
    "CVE-2022-23477",
    "CVE-2022-23478",
    "CVE-2022-23479",
    "CVE-2022-23480",
    "CVE-2022-23481",
    "CVE-2022-23482",
    "CVE-2022-23483",
    "CVE-2022-23484",
    "CVE-2022-23493",
    "CVE-2022-23613",
    "CVE-2023-40184",
    "CVE-2023-42822"
  );
  script_xref(name:"USN", value:"6474-1");

  script_name(english:"Ubuntu 16.04 ESM / 18.04 ESM / 20.04 ESM / 22.04 ESM : xrdp vulnerabilities (USN-6474-1)");

  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 16.04 ESM / 18.04 ESM / 20.04 ESM / 22.04 ESM host has packages installed that are affected by
multiple vulnerabilities as referenced in the USN-6474-1 advisory.

    It was discovered that xrdp incorrectly handled validation of client-supplied data, which could lead to
    out-of-bounds reads. An attacker could possibly use this issue to crash the program or extract sensitive
    information. (CVE-2022-23479, CVE-2022-23481, CVE-2022-23483, CVE-2023-42822)

    It was discovered that xrdp improperly handled session establishment errors. An attacker could potentially
    use this issue to bypass the OS-level session restrictions by PAM. (CVE-2023-40184)

    It was discovered that xrdp incorrectly handled validation of client-supplied data, which could lead to
    out-of-bounds writes. An attacker could possibly use this issue to cause memory corruption or execute
    arbitrary code. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS and Ubuntu 22.04 LTS.
    (CVE-2022-23468)

    It was discovered that xrdp incorrectly handled validation of client-supplied data, which could lead to
    out-of-bounds reads. An attacker could possibly use this issue to crash the program or extract sensitive
    information. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS and Ubuntu 22.04 LTS.
    (CVE-2022-23480, CVE-2022-23482, CVE-2022-23484)

    It was discovered that xrdp incorrectly handled validation of client-supplied data, which could lead to
    out-of-bounds reads. An attacker could possibly use this issue to crash the program or extract sensitive
    information. This issue only affected Ubuntu 20.04 LTS and Ubuntu 22.04 LTS. (CVE-2022-23477,
    CVE-2022-23493)

    It was discovered that xrdp incorrectly handled validation of client-supplied data, which could lead to
    out-of-bounds writes. An attacker could possibly use this issue to cause memory corruption or execute
    arbitrary code. This issue only affected Ubuntu 20.04 LTS and Ubuntu 22.04 LTS. (CVE-2022-23478)

    It was discovered that xrdp incorrectly handled validation of client-supplied data, which could lead to
    out-of-bounds reads. An attacker could possibly use this issue to crash the program or extract sensitive
    information. This issue only affected Ubuntu 22.04 LTS. (CVE-2022-23613)

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-6474-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected xorgxrdp, xrdp and / or xrdp-pulseaudio-installer packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
  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-2022-23613");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2022-23484");

  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:"2022/02/07");
  script_set_attribute(attribute:"patch_publication_date", value:"2023/11/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/11/09");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:esm");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:esm");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04:-:esm");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:22.04:-:esm");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:xorgxrdp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:xrdp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:xrdp-pulseaudio-installer");
  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) 2023-2024 Canonical, Inc. / NASL script (C) 2023-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl", "ubuntu_pro_sub_detect.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 (! ('16.04' >< os_release || '18.04' >< os_release || '20.04' >< os_release || '22.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 16.04 / 18.04 / 20.04 / 22.04', '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 ubuntu_pro_detected = get_kb_item('Host/Ubuntu/Pro/Services/esm-apps');
ubuntu_pro_detected = !empty_or_null(ubuntu_pro_detected);

var pro_caveat_needed = FALSE;

var pkgs = [
    {'osver': '16.04', 'pkgname': 'xrdp', 'pkgver': '0.6.1-2ubuntu0.3+esm3', 'ubuntu_pro': TRUE},
    {'osver': '18.04', 'pkgname': 'xorgxrdp', 'pkgver': '0.9.5-2ubuntu0.1~esm2', 'ubuntu_pro': TRUE},
    {'osver': '18.04', 'pkgname': 'xrdp', 'pkgver': '0.9.5-2ubuntu0.1~esm2', 'ubuntu_pro': TRUE},
    {'osver': '18.04', 'pkgname': 'xrdp-pulseaudio-installer', 'pkgver': '0.9.5-2ubuntu0.1~esm2', 'ubuntu_pro': TRUE},
    {'osver': '20.04', 'pkgname': 'xrdp', 'pkgver': '0.9.12-1ubuntu0.1+esm1', 'ubuntu_pro': TRUE},
    {'osver': '22.04', 'pkgname': 'xrdp', 'pkgver': '0.9.17-2ubuntu2+esm1', 'ubuntu_pro': TRUE}
];

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'];
  var pro_required = NULL;
  if (!empty_or_null(package_array['ubuntu_pro'])) pro_required = package_array['ubuntu_pro'];
  if (osver && pkgname && pkgver) {
    if (ubuntu_check(osver:osver, pkgname:pkgname, pkgver:pkgver)) {
        flag++;
        if (!ubuntu_pro_detected && !pro_caveat_needed) pro_caveat_needed = pro_required;
    }
  }
}

if (flag)
{
  var extra = '';
  if (pro_caveat_needed) {
    extra += 'NOTE: This vulnerability check contains fixes that apply to packages only \n';
    extra += 'available in Ubuntu ESM repositories. Access to these package security updates \n';
    extra += 'require an Ubuntu Pro subscription.\n\n';
  }
  extra += ubuntu_report_get();
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    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, 'xorgxrdp / xrdp / xrdp-pulseaudio-installer');
}