Debian dsa-5872 : xnest - security update

#%NASL_MIN_LEVEL 80900
#
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory dsa-5872. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(216946);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/02/28");

  script_cve_id(
    "CVE-2025-26594",
    "CVE-2025-26595",
    "CVE-2025-26596",
    "CVE-2025-26597",
    "CVE-2025-26598",
    "CVE-2025-26599",
    "CVE-2025-26600",
    "CVE-2025-26601"
  );

  script_name(english:"Debian dsa-5872 : xnest - security update");

  script_set_attribute(attribute:"synopsis", value:
"The remote Debian host is missing one or more security-related updates.");
  script_set_attribute(attribute:"description", value:
"The remote Debian 12 host has packages installed that are affected by multiple vulnerabilities as referenced in the
dsa-5872 advisory.

    - -------------------------------------------------------------------------
    Debian Security Advisory DSA-5872-1                   [email protected]
    https://www.debian.org/security/                     Salvatore Bonaccorso
    February 28, 2025                     https://www.debian.org/security/faq
    - -------------------------------------------------------------------------

    Package        : xorg-server
    CVE ID         : CVE-2025-26594 CVE-2025-26595 CVE-2025-26596 CVE-2025-26597
                     CVE-2025-26598 CVE-2025-26599 CVE-2025-26600 CVE-2025-26601
    Debian Bug     : 1098906

    Jan-Niklas Sohn discovered several vulnerabilities in the Xorg X server,
    which may result in privilege escalation if the X server is running
    privileged.

    For the stable distribution (bookworm), these problems have been fixed in
    version 2:21.1.7-3+deb12u9.

    We recommend that you upgrade your xorg-server packages.

    For the detailed security status of xorg-server please refer to its
    security tracker page at:
    https://security-tracker.debian.org/tracker/xorg-server

    Further information about Debian Security Advisories, how to apply
    these updates to your system and frequently asked questions can be
    found at: https://www.debian.org/security/

    Mailing list: [email protected]

Tenable has extracted the preceding description block directly from the Debian 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://security-tracker.debian.org/tracker/source-package/xorg-server");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-26594");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-26595");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-26596");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-26597");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-26598");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-26599");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-26600");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-26601");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bookworm/xorg-server");
  script_set_attribute(attribute:"solution", value:
"Upgrade the xnest packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/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:L/AC:L/PR:L/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-2025-26601");

  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:"2025/02/25");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/02/28");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/02/28");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:xnest");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:xorg-server-source");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:xserver-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:xserver-xephyr");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:xserver-xorg-core");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:xserver-xorg-core-udeb");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:xserver-xorg-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:xserver-xorg-legacy");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:xvfb");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:12.0");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2025 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Debian/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);
if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);

var debian_release = get_kb_item('Host/Debian/release');
if ( isnull(debian_release) ) audit(AUDIT_OS_NOT, 'Debian');
debian_release = chomp(debian_release);
if (! preg(pattern:"^(12)\.[0-9]+", string:debian_release)) audit(AUDIT_OS_NOT, 'Debian 12.0', 'Debian ' + debian_release);
var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Debian', cpu);

var pkgs = [
    {'release': '12.0', 'prefix': 'xnest', 'reference': '2:21.1.7-3+deb12u9'},
    {'release': '12.0', 'prefix': 'xorg-server-source', 'reference': '2:21.1.7-3+deb12u9'},
    {'release': '12.0', 'prefix': 'xserver-common', 'reference': '2:21.1.7-3+deb12u9'},
    {'release': '12.0', 'prefix': 'xserver-xephyr', 'reference': '2:21.1.7-3+deb12u9'},
    {'release': '12.0', 'prefix': 'xserver-xorg-core', 'reference': '2:21.1.7-3+deb12u9'},
    {'release': '12.0', 'prefix': 'xserver-xorg-core-udeb', 'reference': '2:21.1.7-3+deb12u9'},
    {'release': '12.0', 'prefix': 'xserver-xorg-dev', 'reference': '2:21.1.7-3+deb12u9'},
    {'release': '12.0', 'prefix': 'xserver-xorg-legacy', 'reference': '2:21.1.7-3+deb12u9'},
    {'release': '12.0', 'prefix': 'xvfb', 'reference': '2:21.1.7-3+deb12u9'}
];

var flag = 0;
foreach package_array ( pkgs ) {
  var _release = NULL;
  var prefix = NULL;
  var reference = NULL;
  if (!empty_or_null(package_array['release'])) _release = package_array['release'];
  if (!empty_or_null(package_array['prefix'])) prefix = package_array['prefix'];
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (_release && prefix && reference) {
    if (deb_check(release:_release, prefix:prefix, reference:reference)) flag++;
  }
}

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : deb_report_get()
  );
  exit(0);
}
else
{
  var tested = deb_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'xnest / xorg-server-source / xserver-common / xserver-xephyr / etc');
}