Ubuntu 20.04 LTS / 22.04 LTS / 24.04 LTS : Emacs vulnerabilities (USN-8011-1)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-8011-1. 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(297948);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/02/04");

  script_cve_id("CVE-2024-53920", "CVE-2025-1244");
  script_xref(name:"USN", value:"8011-1");

  script_name(english:"Ubuntu 20.04 LTS / 22.04 LTS / 24.04 LTS : Emacs vulnerabilities (USN-8011-1)");

  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 20.04 LTS / 22.04 LTS / 24.04 LTS host has packages installed that are affected by multiple
vulnerabilities as referenced in the USN-8011-1 advisory.

    It was discovered that Emacs could trigger unsafe Lisp macro expansion, when a user invoked elisp-
    completion-at-point on untrusted Emacs Lisp

    source code. An attacker could possibly use this issue to execute

    arbitrary code. (CVE-2024-53920)

    It was discovered that Emacs did not properly sanitize input when

    handling certain URI schemes. An attacker could possibly use this issue to execute arbitrary shell
    commands by tricking a user into opening a

    specially crafted URL. (CVE-2025-1244)

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-8011-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected 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:R/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-2025-1244");

  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:"2024/11/27");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/02/04");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/02/04");

  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:"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:"p-cpe:/a:canonical:ubuntu_linux:emacs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:emacs-bin-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:emacs-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:emacs-el");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:emacs-gtk");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:emacs-lucid");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:emacs-nox");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:emacs-pgtk");
  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 (! ('20.04' >< os_release || '22.04' >< os_release || '24.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 20.04 / 22.04 / 24.04', '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': '20.04', 'pkgname': 'emacs', 'pkgver': '1:26.3+1-1ubuntu2+esm2', 'ubuntu_pro': TRUE},
    {'osver': '20.04', 'pkgname': 'emacs-bin-common', 'pkgver': '1:26.3+1-1ubuntu2+esm2', 'ubuntu_pro': TRUE},
    {'osver': '20.04', 'pkgname': 'emacs-common', 'pkgver': '1:26.3+1-1ubuntu2+esm2', 'ubuntu_pro': TRUE},
    {'osver': '20.04', 'pkgname': 'emacs-el', 'pkgver': '1:26.3+1-1ubuntu2+esm2', 'ubuntu_pro': TRUE},
    {'osver': '20.04', 'pkgname': 'emacs-gtk', 'pkgver': '1:26.3+1-1ubuntu2+esm2', 'ubuntu_pro': TRUE},
    {'osver': '20.04', 'pkgname': 'emacs-lucid', 'pkgver': '1:26.3+1-1ubuntu2+esm2', 'ubuntu_pro': TRUE},
    {'osver': '20.04', 'pkgname': 'emacs-nox', 'pkgver': '1:26.3+1-1ubuntu2+esm2', 'ubuntu_pro': TRUE},
    {'osver': '22.04', 'pkgname': 'emacs', 'pkgver': '1:27.1+1-3ubuntu5.2+esm1', 'ubuntu_pro': TRUE},
    {'osver': '22.04', 'pkgname': 'emacs-bin-common', 'pkgver': '1:27.1+1-3ubuntu5.2+esm1', 'ubuntu_pro': TRUE},
    {'osver': '22.04', 'pkgname': 'emacs-common', 'pkgver': '1:27.1+1-3ubuntu5.2+esm1', 'ubuntu_pro': TRUE},
    {'osver': '22.04', 'pkgname': 'emacs-el', 'pkgver': '1:27.1+1-3ubuntu5.2+esm1', 'ubuntu_pro': TRUE},
    {'osver': '22.04', 'pkgname': 'emacs-gtk', 'pkgver': '1:27.1+1-3ubuntu5.2+esm1', 'ubuntu_pro': TRUE},
    {'osver': '22.04', 'pkgname': 'emacs-lucid', 'pkgver': '1:27.1+1-3ubuntu5.2+esm1', 'ubuntu_pro': TRUE},
    {'osver': '22.04', 'pkgname': 'emacs-nox', 'pkgver': '1:27.1+1-3ubuntu5.2+esm1', 'ubuntu_pro': TRUE},
    {'osver': '24.04', 'pkgname': 'emacs', 'pkgver': '1:29.3+1-1ubuntu2+esm3', 'ubuntu_pro': TRUE},
    {'osver': '24.04', 'pkgname': 'emacs-bin-common', 'pkgver': '1:29.3+1-1ubuntu2+esm3', 'ubuntu_pro': TRUE},
    {'osver': '24.04', 'pkgname': 'emacs-common', 'pkgver': '1:29.3+1-1ubuntu2+esm3', 'ubuntu_pro': TRUE},
    {'osver': '24.04', 'pkgname': 'emacs-el', 'pkgver': '1:29.3+1-1ubuntu2+esm3', 'ubuntu_pro': TRUE},
    {'osver': '24.04', 'pkgname': 'emacs-gtk', 'pkgver': '1:29.3+1-1ubuntu2+esm3', 'ubuntu_pro': TRUE},
    {'osver': '24.04', 'pkgname': 'emacs-lucid', 'pkgver': '1:29.3+1-1ubuntu2+esm3', 'ubuntu_pro': TRUE},
    {'osver': '24.04', 'pkgname': 'emacs-nox', 'pkgver': '1:29.3+1-1ubuntu2+esm3', 'ubuntu_pro': TRUE},
    {'osver': '24.04', 'pkgname': 'emacs-pgtk', 'pkgver': '1:29.3+1-1ubuntu2+esm3', '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'];
  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, 'emacs / emacs-bin-common / emacs-common / emacs-el / emacs-gtk / etc');
}