Debian dla-4527 : inetutils-ftp - security update

#%NASL_MIN_LEVEL 80900
#
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory dla-4527. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(307667);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/23");

  script_cve_id(
    "CVE-2026-24061",
    "CVE-2026-28372",
    "CVE-2026-32746",
    "CVE-2026-32772"
  );
  script_xref(name:"CISA-KNOWN-EXPLOITED", value:"2026/02/16");

  script_name(english:"Debian dla-4527 : inetutils-ftp - 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 11 host has packages installed that are affected by multiple vulnerabilities as referenced in the
dla-4527 advisory.

    -------------------------------------------------------------------------
    Debian LTS Advisory DLA-4527-1                [email protected]
    https://www.debian.org/lts/security/                   Andreas Henriksson
    April 11, 2026                                https://wiki.debian.org/LTS
    -------------------------------------------------------------------------

    Package        : inetutils
    Version        : 2:2.0-1+deb11u4
    CVE ID         : CVE-2026-28372 CVE-2026-32746 CVE-2026-32772
    Debian Bug     : 1130741 1130742

    Several vulnerabilities were discovered in the inetutils implementation
    of telnetd and telnet, which may result in privilege escalation or
    information disclosure.

    CVE-2026-28372

        Ron Ben Yizhak from SafeBreach found that the fix for CVE-2026-24061 was
        not complete and can be exploited by abusing systemd service credentials
        support added to the login(1) implementation of util-linux in release 2.40.

        While Debian bullseye does not include util-linux 2.40 this problem does
        thus not affect it, but was still addressed in case someone manually
        updates util-linux and thus exposes this vulnerability.

    CVE-2026-32746

         Adiel Sol, Arad Inbar, Erez Cohen, Nir Somech, Ben Grinberg, Daniel Lubel
         of DREAM Security Research Team found that the telnetd server has a buffer
         overflow in the LINEMODE SLC (Set Local Characters) suboption handler.
         This can lead to potential pre-login remote code execution.

    CVE-2026-32772

        Justin Swartz discovered that telnet allows servers to read arbitrary
        environment variables from clients via NEW_ENVIRON SEND USERVAR.
        This can lead to information disclosure.

    For Debian 11 bullseye, these problems have been fixed in version
    2:2.0-1+deb11u4.

    We recommend that you upgrade your inetutils packages.

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

    Further information about Debian LTS security advisories, how to apply
    these updates to your system and frequently asked questions can be
    found at: https://wiki.debian.org/LTS
    Attachment:
    signature.asc
    Description: PGP signature

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/inetutils");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-24061");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-28372");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-32746");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-32772");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bullseye/inetutils");
  script_set_attribute(attribute:"solution", value:
"Upgrade the inetutils-ftp 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:F/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:F/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-28372");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"exploit_framework_core", value:"true");
  script_set_attribute(attribute:"metasploit_name", value:'GNU Inetutils Telnet Authentication Bypass Exploit CVE-2026-24061');
  script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/01/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/04/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/21");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:inetutils-ftp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:inetutils-ftpd");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:inetutils-inetd");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:inetutils-ping");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:inetutils-syslogd");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:inetutils-talk");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:inetutils-talkd");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:inetutils-telnet");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:inetutils-telnetd");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:inetutils-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:inetutils-traceroute");
  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) 2026 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:"^(11)\.[0-9]+", string:debian_release)) audit(AUDIT_OS_NOT, 'Debian 11.0', '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': '11.0', 'prefix': 'inetutils-ftp', 'reference': '2:2.0-1+deb11u4'},
    {'release': '11.0', 'prefix': 'inetutils-ftpd', 'reference': '2:2.0-1+deb11u4'},
    {'release': '11.0', 'prefix': 'inetutils-inetd', 'reference': '2:2.0-1+deb11u4'},
    {'release': '11.0', 'prefix': 'inetutils-ping', 'reference': '2:2.0-1+deb11u4'},
    {'release': '11.0', 'prefix': 'inetutils-syslogd', 'reference': '2:2.0-1+deb11u4'},
    {'release': '11.0', 'prefix': 'inetutils-talk', 'reference': '2:2.0-1+deb11u4'},
    {'release': '11.0', 'prefix': 'inetutils-talkd', 'reference': '2:2.0-1+deb11u4'},
    {'release': '11.0', 'prefix': 'inetutils-telnet', 'reference': '2:2.0-1+deb11u4'},
    {'release': '11.0', 'prefix': 'inetutils-telnetd', 'reference': '2:2.0-1+deb11u4'},
    {'release': '11.0', 'prefix': 'inetutils-tools', 'reference': '2:2.0-1+deb11u4'},
    {'release': '11.0', 'prefix': 'inetutils-traceroute', 'reference': '2:2.0-1+deb11u4'}
];

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, 'inetutils-ftp / inetutils-ftpd / inetutils-inetd / inetutils-ping / etc');
}