Azure Linux 3.0 Security Update: libxml2 (CVE-2025-6170)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(243026);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/01/21");

  script_cve_id("CVE-2025-6170");
  script_xref(name:"IAVA", value:"2025-A-0707-S");

  script_name(english:"Azure Linux 3.0 Security Update: libxml2 (CVE-2025-6170)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Azure Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The version of libxml2 installed on the remote Azure Linux 3.0 host is prior to tested version. It is, therefore,
affected by a vulnerability as referenced in the CVE-2025-6170 advisory.

  - A flaw was found in the interactive shell of the xmllint command-line tool, used for parsing XML files.
    When a user inputs an overly long command, the program does not check the input size properly, which can
    cause it to crash. This issue might allow attackers to run harmful code in rare configurations without
    modern protections. (CVE-2025-6170)

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://nvd.nist.gov/vuln/detail/CVE-2025-6170");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:H/Au:N/C:N/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2025-6170");

  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:"2025/06/16");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/07/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/07/30");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:libxml2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:libxml2-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:libxml2-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:python3-libxml2");
  script_set_attribute(attribute:"cpe", value:"x-cpe:/o:microsoft:azure_linux");
  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:"Azure Linux Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2025-2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info2.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/AzureLinux/release", "Host/AzureLinux/rpm-list", "Host/cpu");

  exit(0);
}
include('rpm.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var release = get_kb_item('Host/AzureLinux/release');
if (isnull(release) || 'Azure Linux' >!< release) audit(AUDIT_OS_NOT, 'Azure Linux');
var os_ver = pregmatch(pattern: "Azure Linux ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'Azure Linux');
os_ver = os_ver[1];
if (! preg(pattern:"^3([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, 'Azure Linux 3.0', 'Azure Linux ' + os_ver);

if (!get_kb_item('Host/AzureLinux/rpm-list')) 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$" && 'aarch64' >!< cpu)
  audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Azure Linux', cpu);

var pkgs = [
    {'reference':'libxml2-2.11.5-6.azl3', 'cpu':'aarch64', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libxml2-2.11.5-6.azl3', 'cpu':'x86_64', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libxml2-debuginfo-2.11.5-6.azl3', 'cpu':'aarch64', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libxml2-debuginfo-2.11.5-6.azl3', 'cpu':'x86_64', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libxml2-devel-2.11.5-6.azl3', 'cpu':'aarch64', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libxml2-devel-2.11.5-6.azl3', 'cpu':'x86_64', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python3-libxml2-2.11.5-6.azl3', 'cpu':'aarch64', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python3-libxml2-2.11.5-6.azl3', 'cpu':'x86_64', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE}
];

var flag = 0;
foreach var package_array ( pkgs ) {
  var reference = NULL;
  var _release = NULL;
  var sp = NULL;
  var _cpu = NULL;
  var el_string = NULL;
  var rpm_spec_vers_cmp = NULL;
  var epoch = NULL;
  var allowmaj = NULL;
  var exists_check = NULL;
  var cves = NULL;
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (!empty_or_null(package_array['release'])) _release = 'Azure Linux ' + package_array['release'];
  if (!empty_or_null(package_array['sp'])) sp = package_array['sp'];
  if (!empty_or_null(package_array['cpu'])) _cpu = package_array['cpu'];
  if (!empty_or_null(package_array['el_string'])) el_string = package_array['el_string'];
  if (!empty_or_null(package_array['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = package_array['rpm_spec_vers_cmp'];
  if (!empty_or_null(package_array['epoch'])) epoch = package_array['epoch'];
  if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
  if (!empty_or_null(package_array['exists_check'])) exists_check = package_array['exists_check'];
  if (!empty_or_null(package_array['cves'])) cves = package_array['cves'];
  if (reference && _release && (!exists_check || rpm_exists(release:_release, rpm:exists_check))) {
    if (rpm_check(release:_release, 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_NOTE,
      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, 'libxml2 / libxml2-debuginfo / libxml2-devel / python3-libxml2');
}