Unity Linux 20.1050a / 20.1060a / 20.1070a Security Update: thunderbird (UTSA-2026-100885)

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

include('compat.inc');

if (description)
{
  script_id(336498);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/17");

  script_cve_id("CVE-2025-5986");

  script_name(english:"Unity Linux 20.1050a / 20.1060a / 20.1070a Security Update: thunderbird (UTSA-2026-100885)");

  script_set_attribute(attribute:"synopsis", value:
"The Unity Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the
UTSA-2026-100885 advisory.

    A crafted HTML email using mailbox:/// links can trigger automatic, unsolicited downloads of .pdf files to
    the user's desktop or home directory without prompting, even if auto-saving is disabled. This behavior can
    be abused to fill the disk with garbage data (e.g. using /dev/urandom on Linux) or to leak Windows
    credentials via SMB links when the email is viewed in HTML mode. While user interaction is required to
    download the .pdf file, visual obfuscation can conceal the download trigger. Viewing the email in HTML
    mode is enough to load external content. This vulnerability was fixed in Thunderbird 128.11.1 and
    Thunderbird 139.0.2.

Tenable has extracted the preceding description block directly from the Unity 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.");
  # https://src.uniontech.com/#/security_advisory_detail?utsa_id=UTSA-2026-100885
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?986225b2");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/security/cve/CVE-2025-5986");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2025-5986");
  script_set_attribute(attribute:"solution", value:
"Update the affected thunderbird package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/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:N/UI:R/S:U/C:N/I:N/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-2025-5986");

  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:"2025/06/10");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/08/14");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/17");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Unity Linux 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_info2.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/UOS-Server/release", "Host/UOS-Server/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) || 'UOS Server' >!< os_product) audit(AUDIT_OS_NOT, 'UOS Server');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'UOS Server');
if (! preg(pattern:"^20.1050a|20.1060a|20.1070a([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 20.1050a / 20.1060a / 20.1070a', 'UOS Server ' + os_version);

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

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('aarch64' >!< cpu && 'amd64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1050a',
    'pkgs': [
      {'reference':'thunderbird-140.13.0-1.0.1.uelc20.01', 'sp':'1050a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE},
      {'reference':'thunderbird-140.13.0-1.0.1.uelc20.01', 'sp':'1050a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE},
      {'reference':'thunderbird-140.13.0-1.0.1.uelc20.01', 'sp':'1050a', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE}
    ]
  },
  {
    'release': '20',
    'sp': '1060a',
    'pkgs': [
      {'reference':'thunderbird-140.13.0-1.0.1.uelc20.01', 'sp':'1060a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE},
      {'reference':'thunderbird-140.13.0-1.0.1.uelc20.01', 'sp':'1060a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE},
      {'reference':'thunderbird-140.13.0-1.0.1.uelc20.01', 'sp':'1060a', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE}
    ]
  },
  {
    'release': '20',
    'sp': '1070a',
    'pkgs': [
      {'reference':'thunderbird-140.13.0-1.0.1.uelc20.01', 'sp':'1070a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE},
      {'reference':'thunderbird-140.13.0-1.0.1.uelc20.01', 'sp':'1070a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE},
      {'reference':'thunderbird-140.13.0-1.0.1.uelc20.01', 'sp':'1070a', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE}
    ]
  }
];

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, 'thunderbird');
}