Debian dla-4156 : openssh-client - 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-4156. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(235598);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/10/29");

  script_cve_id("CVE-2025-32728");
  script_xref(name:"IAVA", value:"2025-A-0258-S");

  script_name(english:"Debian dla-4156 : openssh-client - security update");

  script_set_attribute(attribute:"synopsis", value:
"The remote Debian host is missing a security-related update.");
  script_set_attribute(attribute:"description", value:
"The remote Debian 11 host has packages installed that are affected by a vulnerability as referenced in the dla-4156
advisory.

    -------------------------------------------------------------------------
    Debian LTS Advisory DLA-4156-1                [email protected]
    https://www.debian.org/lts/security/                         Colin Watson
    May 08, 2025                                  https://wiki.debian.org/LTS
    -------------------------------------------------------------------------

    Package        : openssh
    Version        : 1:8.4p1-5+deb11u5
    CVE ID         : CVE-2025-32728
    Debian Bug     : 1102603

    Tim Rice discovered that the DisableForwarding directive was documented
    as disabling X11 and agent forwarding but it failed to do so.


    For Debian 11 bullseye, this problem has been fixed in version
    1:8.4p1-5+deb11u5.

    We recommend that you upgrade your openssh packages.

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

    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 this issue 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/openssh");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-32728");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bullseye/openssh");
  script_set_attribute(attribute:"solution", value:
"Upgrade the openssh-client packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:N/I:P/A:N");
  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:N/UI:N/S:C/C:N/I:L/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2025-32728");

  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:"2025/04/08");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/05/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/05/08");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:openssh-client");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:openssh-client-udeb");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:openssh-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:openssh-server-udeb");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:openssh-sftp-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:openssh-tests");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:ssh");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:ssh-askpass-gnome");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_set_attribute(attribute:"stig_severity", value:"I");
  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:"^(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': 'openssh-client', 'reference': '1:8.4p1-5+deb11u5'},
    {'release': '11.0', 'prefix': 'openssh-client-udeb', 'reference': '1:8.4p1-5+deb11u5'},
    {'release': '11.0', 'prefix': 'openssh-server', 'reference': '1:8.4p1-5+deb11u5'},
    {'release': '11.0', 'prefix': 'openssh-server-udeb', 'reference': '1:8.4p1-5+deb11u5'},
    {'release': '11.0', 'prefix': 'openssh-sftp-server', 'reference': '1:8.4p1-5+deb11u5'},
    {'release': '11.0', 'prefix': 'openssh-tests', 'reference': '1:8.4p1-5+deb11u5'},
    {'release': '11.0', 'prefix': 'ssh', 'reference': '1:8.4p1-5+deb11u5'},
    {'release': '11.0', 'prefix': 'ssh-askpass-gnome', 'reference': '1:8.4p1-5+deb11u5'}
];

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_NOTE,
    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, 'openssh-client / openssh-client-udeb / openssh-server / etc');
}