Ubuntu 20.04 LTS / 24.04 LTS / 26.04 LTS : FastNetMon vulnerabilities (USN-8429-1)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-8429-1. 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(321184);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/06/16");

  script_cve_id(
    "CVE-2026-48686",
    "CVE-2026-48687",
    "CVE-2026-48689",
    "CVE-2026-48691",
    "CVE-2026-48694"
  );
  script_xref(name:"USN", value:"8429-1");

  script_name(english:"Ubuntu 20.04 LTS / 24.04 LTS / 26.04 LTS : FastNetMon vulnerabilities (USN-8429-1)");

  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 / 24.04 LTS / 26.04 LTS host has a package installed that is affected by multiple
vulnerabilities as referenced in the USN-8429-1 advisory.

    It was discovered that FastNetMon incorrectly validated prefix lengths when decoding BGP NLRI data. A
    remote attacker could possibly use this issue to cause a denial of service or execute arbitrary code. This
    issue only affected Ubuntu 24.04 LTS and Ubuntu 26.04 LTS. (CVE-2026-48686)

    It was discovered that FastNetMon incorrectly sanitized input in the Juniper router integration plugin. An
    attacker could possibly use this issue to execute arbitrary commands. (CVE-2026-48687)

    It was discovered that FastNetMon incorrectly handled buffer bounds checks when processing network
    traffic. A remote attacker could possibly use this issue to cause a denial of service or execute arbitrary
    code. This issue only affected Ubuntu 24.04 LTS and Ubuntu 26.04 LTS. (CVE-2026-48689)

    It was discovered that FastNetMon incorrectly handled encoding the BGP AS_PATH attribute. A remote
    attacker could possibly use this issue to cause a denial of service or execute arbitrary code. This issue
    only affected Ubuntu 24.04 LTS and Ubuntu 26.04 LTS. (CVE-2026-48691)

    It was discovered that FastNetMon incorrectly validated IP address input in the Juniper router integration
    plugin. An attacker could possibly use this issue to inject arbitrary router configuration commands.
    (CVE-2026-48694)

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-8429-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected fastnetmon package.");
  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:POC/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:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-48691");

  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:"2026/05/26");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/06/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/06/16");

  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:24.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:26.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:fastnetmon");
  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 || '24.04' >< os_release || '26.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 20.04 / 24.04 / 26.04', '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': 'fastnetmon', 'pkgver': '1.1.4-1ubuntu0.1~esm1', 'ubuntu_pro': TRUE, 'cves': ['CVE-2026-48687', 'CVE-2026-48694']},
    {'osver': '24.04', 'pkgname': 'fastnetmon', 'pkgver': '1.2.6-1ubuntu0.1~esm1', 'ubuntu_pro': TRUE, 'cves': ['CVE-2026-48686', 'CVE-2026-48687', 'CVE-2026-48689', 'CVE-2026-48691', 'CVE-2026-48694']},
    {'osver': '26.04', 'pkgname': 'fastnetmon', 'pkgver': '1.2.8+git20250911-2ubuntu0.1~esm1', 'ubuntu_pro': TRUE, 'cves': ['CVE-2026-48686', 'CVE-2026-48687', 'CVE-2026-48689', 'CVE-2026-48691', 'CVE-2026-48694']}
];

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, 'fastnetmon');
}