Unity Linux 20.1050e / 20.1070e Security Update: kernel (UTSA-2026-010820)

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

include('compat.inc');

if (description)
{
  script_id(308820);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/22");

  script_cve_id("CVE-2025-38066");

  script_name(english:"Unity Linux 20.1050e / 20.1070e Security Update: kernel (UTSA-2026-010820)");

  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-2026-010820 advisory.

    In the Linux kernel, the following vulnerability has been resolved:

    dm cache: prevent BUG_ON by blocking retries on failed device resumes

    A cache device failing to resume due to mapping errors should not be
    retried, as the failure leaves a partially initialized policy object.
    Repeating the resume operation risks triggering BUG_ON when reloading
    cache mappings into the incomplete policy object.

    Reproduce steps:

    1. create a cache metadata consisting of 512 or more cache blocks,
       with some mappings stored in the first array block of the mapping
       array. Here we use cache_restore v1.0 to build the metadata.

    cat <<EOF >> cmeta.xml
    <superblock uuid= block_size=128 nr_cache_blocks=512 \
    policy=smq hint_width=4>
      <mappings>
        <mapping cache_block=0 origin_block=0 dirty=false/>
      </mappings>
    </superblock>
    EOF
    dmsetup create cmeta --table 0 8192 linear /dev/sdc 0
    cache_restore -i cmeta.xml -o /dev/mapper/cmeta --metadata-version=2
    dmsetup remove cmeta

    2. wipe the second array block of the mapping array to simulate
       data degradations.

    mapping_root=$(dd if=/dev/sdc bs=1c count=8 skip=192 \
    2>/dev/null | hexdump -e '1/8 %u\n')
    ablock=$(dd if=/dev/sdc bs=1c count=8 skip=$((4096*mapping_root+2056)) \
    2>/dev/null | hexdump -e '1/8 %u\n')
    dd if=/dev/zero of=/dev/sdc bs=4k count=1 seek=$ablock

    3. try bringing up the cache device. The resume is expected to fail
       due to the broken array block.

    dmsetup create cmeta --table 0 8192 linear /dev/sdc 0
    dmsetup create cdata --table 0 65536 linear /dev/sdc 8192
    dmsetup create corig --table 0 524288 linear /dev/sdc 262144
    dmsetup create cache --notable
    dmsetup load cache --table 0 524288 cache /dev/mapper/cmeta \
    /dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0
    dmsetup resume cache

    4. try resuming the cache again. An unexpected BUG_ON is triggered
       while loading cache mappings.

    dmsetup resume cache

    Kernel logs:

    (snip)
    ------------[ cut here ]------------
    kernel BUG at drivers/md/dm-cache-policy-smq.c:752!
    Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
    CPU: 0 UID: 0 PID: 332 Comm: dmsetup Not tainted 6.13.4 #3
    RIP: 0010:smq_load_mapping+0x3e5/0x570

    Fix by disallowing resume operations for devices that failed the
    initial attempt.

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-2026-010820
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?691a4063");
  # https://lore.kernel.org/linux-cve-announce/2025061837-CVE-2025-38066-b3f6@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?01056468");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2025-38066");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/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:L/AC:L/PR:L/UI:N/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-2025-38066");

  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:"2025/06/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/04/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/21");

  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:"^20.1050e|20.1070e([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 20.1050e / 20.1070e', '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 && 'sw_64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1050e',
    'pkgs': [
      {'reference':'kernel-5.10.0-27.5', 'sp':'1050e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-27.5', 'sp':'1050e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-27.5', 'sp':'1050e', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  },
  {
    'release': '20',
    'sp': '1070e',
    'pkgs': [
      {'reference':'kernel-5.10.0-79.7.1', 'sp':'1070e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.7.1', 'sp':'1070e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.7.1', 'sp':'1070e', 'cpu':'sw_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.7.1', 'sp':'1070e', 'cpu':'x86_64', 'rpm_spec_vers_cmp':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_WARNING,
      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, 'kernel');
}