Debian DSA-5409-1 : libssh - 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-5409. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(176333);
  script_version("1.5");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/01/24");

  script_cve_id("CVE-2023-1667", "CVE-2023-2283");
  script_xref(name:"IAVA", value:"2023-A-0517-S");

  script_name(english:"Debian DSA-5409-1 : libssh - 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
dsa-5409 advisory.

    Two security issues have been discovered in libssh, a tiny C SSH library: CVE-2023-1667 Philip Turnbull
    discovered a NULL pointer dereference which could result in denial of service. CVE-2023-2283 Kevin
    Backhouse discovered that pki_verify_data_signature() may fail to correctly validate authentication in
    memory pressure situations. For the stable distribution (bullseye), these problems have been fixed in
    version 0.9.7-0+deb11u1. We recommend that you upgrade your libssh packages. For the detailed security
    status of libssh please refer to its security tracker page at: https://security-
    tracker.debian.org/tracker/libssh

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://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1035832");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/source-package/libssh");
  script_set_attribute(attribute:"see_also", value:"https://www.debian.org/security/2023/dsa-5409");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2023-1667");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2023-2283");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bullseye/libssh");
  script_set_attribute(attribute:"solution", value:
"Upgrade the libssh packages.

For the stable distribution (bullseye), these problems have been fixed in version 0.9.7-0+deb11u1.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:N");
  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:L/I:L/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2023-2283");

  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:"2023/05/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2023/05/23");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/05/24");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libssh-4");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libssh-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libssh-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libssh-gcrypt-4");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libssh-gcrypt-dev");
  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:"II");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2023-2025 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': 'libssh-4', 'reference': '0.9.7-0+deb11u1'},
    {'release': '11.0', 'prefix': 'libssh-dev', 'reference': '0.9.7-0+deb11u1'},
    {'release': '11.0', 'prefix': 'libssh-doc', 'reference': '0.9.7-0+deb11u1'},
    {'release': '11.0', 'prefix': 'libssh-gcrypt-4', 'reference': '0.9.7-0+deb11u1'},
    {'release': '11.0', 'prefix': 'libssh-gcrypt-dev', 'reference': '0.9.7-0+deb11u1'}
];

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, 'libssh-4 / libssh-dev / libssh-doc / libssh-gcrypt-4 / etc');
}