Alibaba Cloud Linux 3 : 0189: libssh (ALINUX3-SA-2025:0189)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The package checks in this plugin were extracted from
# Alibaba Cloud Linux Security Advisory ALINUX3-SA-2025:0189.
##

include('compat.inc');

if (description)
{
  script_id(277151);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/12/03");

  script_cve_id("CVE-2025-5372");

  script_name(english:"Alibaba Cloud Linux 3 : 0189: libssh (ALINUX3-SA-2025:0189)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Alibaba Cloud Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Alibaba Cloud Linux 3 host has packages installed that are affected by a vulnerability as referenced in the
ALINUX3-SA-2025:0189 advisory.

    Package updates are available for Alibaba Cloud Linux 3 that fix the following vulnerabilities:

    CVE-2025-5372:
    A flaw was found in libssh versions built with OpenSSL versions older than 3.0, specifically in the
    ssh_kdf() function responsible for key derivation. Due to inconsistent interpretation of return values
    where OpenSSL uses 0 to indicate failure and libssh uses 0 for successthe function may mistakenly
    return a success status even when key derivation fails. This results in uninitialized cryptographic key
    buffers being used in subsequent communication, potentially compromising SSH sessions' confidentiality,
    integrity, and availability.

Tenable has extracted the preceding description block directly from the Alibaba Cloud Linux 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:"http://mirrors.aliyun.com/alinux/3/cve/alinux3-sa-20250189.xml");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/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:L/UI:N/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-2025-5372");

  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:"2025/07/03");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/11/26");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/12/03");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:libssh");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:libssh-config");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:libssh-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:libssh-debugsource");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:libssh-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:libssh-doc");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alibabacloud:alibaba_cloud_linux_3");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Alibaba Cloud Linux 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/Alibaba/release", "Host/Alibaba/rpm-list", "Host/cpu");

  exit(0);
}


include('rpm2.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_product = get_kb_item('installed_os/local/SSH/0/product');
if (isnull(os_product) || 'Alibaba Cloud Linux' >!< os_product) audit(AUDIT_OS_NOT, 'Alibaba Cloud Linux');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'Alibaba Cloud Linux');
if (! preg(pattern:"^3([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'Alibaba Cloud Linux 3.x', 'Alibaba Cloud Linux ' + os_version);

if (!get_kb_item('Host/Alibaba/rpm-list')) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('aarch64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Alibaba Cloud Linux', cpu);

var constraints = [
  {
    'release': '3',
    'pkgs': [
      {'reference':'libssh-0.9.6-16.0.1.al8', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'libssh-0.9.6-16.0.1.al8', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'libssh-config-0.9.6-16.0.1.al8', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'libssh-debuginfo-0.9.6-16.0.1.al8', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'libssh-debuginfo-0.9.6-16.0.1.al8', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'libssh-debugsource-0.9.6-16.0.1.al8', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'libssh-debugsource-0.9.6-16.0.1.al8', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'libssh-devel-0.9.6-16.0.1.al8', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'libssh-devel-0.9.6-16.0.1.al8', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'libssh-doc-0.9.6-16.0.1.al8', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'}
    ]
  }
];

var os_release = get_one_kb_item('installed_os/local/SSH/0/release');
var os_sp = get_one_kb_item('Host/*/minor_release');

var flag = 0;
var reference;
var sp;
var _cpu;
var el_string;
var rpm_spec_vers_cmp;
var epoch;
var allowmaj;
var exists_check;
var cves;
foreach var constraint ( constraints ) {
  # Check that the target release is equal to the affected release
  if (!empty_or_null(constraint['release'])){
    if (constraint['release'] != os_release) continue;
  }
  if (!empty_or_null(constraint['sp'])){
    if (constraint['sp'] != os_sp) continue;
  }
  foreach var pkg ( constraint['pkgs'] ) {
    reference = NULL;
    sp = NULL;
    _cpu = NULL;
    el_string = NULL;
    rpm_spec_vers_cmp = NULL;
    epoch = NULL;
    allowmaj = NULL;
    exists_check = NULL;
    cves = NULL;
    if (!empty_or_null(pkg['reference'])) reference = pkg['reference'];
    if (!empty_or_null(pkg['sp'])) sp = pkg['sp'];
    if (!empty_or_null(pkg['cpu'])) _cpu = pkg['cpu'];
    if (!empty_or_null(pkg['el_string'])) el_string = pkg['el_string'];
    if (!empty_or_null(pkg['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = pkg['rpm_spec_vers_cmp'];
    if (!empty_or_null(pkg['epoch'])) epoch = pkg['epoch'];
    if (!empty_or_null(pkg['allowmaj'])) allowmaj = pkg['allowmaj'];
    if (!empty_or_null(pkg['exists_check'])) exists_check = pkg['exists_check'];
    if (!empty_or_null(pkg['cves'])) cves = pkg['cves'];
    if (reference &&
        ## (no known rpm to check OR known rpm_exists)
        (!exists_check || rpm_exists(rpm:exists_check)) &&
        rpm_check(sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj, cves:cves)) flag++;
  }
}

if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'libssh / libssh-config / libssh-debuginfo / libssh-debugsource / etc');
}