Ubuntu 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 25.10 : xrdp vulnerabilities (USN-8476-1)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-8476-1. 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(322953);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/06/26");

  script_cve_id(
    "CVE-2023-40184",
    "CVE-2023-42822",
    "CVE-2024-39917",
    "CVE-2025-68670"
  );
  script_xref(name:"USN", value:"8476-1");

  script_name(english:"Ubuntu 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 25.10 : xrdp vulnerabilities (USN-8476-1)");

  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 / 22.04 LTS / 24.04 LTS / 25.10 host has packages installed that are affected by
multiple vulnerabilities as referenced in the USN-8476-1 advisory.

    It was discovered that xrdp incorrectly handled bounds checking when processing user domain information
    during the connection sequence. An unauthenticated remote attacker could use this issue to cause xrdp to
    crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2025-68670)

    It was discovered that xrdp did not correctly enforce the maximum number of login attempts configured by
    the MaxLoginRetry parameter. A remote attacker could use this issue to perform an unlimited number of
    login attempts. (CVE-2024-39917)

    It was discovered that xrdp did not perform bounds checking when accessing font glyphs. Since some of this
    data is controllable by the user, a remote attacker could use this issue to cause xrdp to read out of
    bounds. This issue only affected Ubuntu 24.04 LTS. (CVE-2023-42822)

    It was discovered that xrdp did not properly handle session establishment errors. A remote attacker could
    use this issue to bypass OS-level session restrictions enforced by PAM, such as the maximum number of
    concurrent sessions per user. This issue only affected Ubuntu 24.04 LTS. (CVE-2023-40184)

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-8476-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected xorgxrdp, xrdp and / or xrdp-pulseaudio-installer packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/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-2025-68670");

  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:"2023/08/30");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/06/25");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/06/26");

  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:"cpe:/o:canonical:ubuntu_linux:22.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:24.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:25.10");
  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) 2026 Canonical, Inc. / NASL script (C) 2026 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 (! ('18.04' >< os_release || '20.04' >< os_release || '22.04' >< os_release || '24.04' >< os_release || '25.10' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 18.04 / 20.04 / 22.04 / 24.04 / 25.10', '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': '18.04', 'pkgname': 'xorgxrdp', 'pkgver': '0.9.5-2ubuntu0.1~esm3', 'ubuntu_pro': TRUE, 'cves': ['CVE-2024-39917', 'CVE-2025-68670']},
    {'osver': '18.04', 'pkgname': 'xrdp', 'pkgver': '0.9.5-2ubuntu0.1~esm3', 'ubuntu_pro': TRUE, 'cves': ['CVE-2024-39917', 'CVE-2025-68670']},
    {'osver': '18.04', 'pkgname': 'xrdp-pulseaudio-installer', 'pkgver': '0.9.5-2ubuntu0.1~esm3', 'ubuntu_pro': TRUE, 'cves': ['CVE-2024-39917', 'CVE-2025-68670']},
    {'osver': '20.04', 'pkgname': 'xrdp', 'pkgver': '0.9.12-1ubuntu0.1+esm2', 'ubuntu_pro': TRUE, 'cves': ['CVE-2024-39917', 'CVE-2025-68670']},
    {'osver': '22.04', 'pkgname': 'xrdp', 'pkgver': '0.9.17-2ubuntu3+esm2', 'ubuntu_pro': TRUE, 'cves': ['CVE-2024-39917', 'CVE-2025-68670']},
    {'osver': '24.04', 'pkgname': 'xrdp', 'pkgver': '0.9.24-4ubuntu0.1~esm1', 'ubuntu_pro': TRUE, 'cves': ['CVE-2023-40184', 'CVE-2023-42822', 'CVE-2024-39917', 'CVE-2025-68670']},
    {'osver': '25.10', 'pkgname': 'xrdp', 'pkgver': '0.10.1-3.1+deb13u1build0.25.10.1', 'ubuntu_pro': FALSE, 'cves': ['CVE-2024-39917', 'CVE-2025-68670']}
];

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 (!empty_or_null(package_array['cves'])) cves = package_array['cves'];
  var pro_required = NULL;
  if (!empty_or_null(package_array['ubuntu_pro'])) pro_required = package_array['ubuntu_pro'];
  if (osver && pkgname && pkgver) {
    if (deb_check(release:osver, prefix:pkgname, reference:pkgver, cves:cves)) {
        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');
}