Unity Linux 20.1070e Security Update: kernel (UTSA-2026-005499)

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

include('compat.inc');

if (description)
{
  script_id(300872);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/03/05");

  script_cve_id("CVE-2023-53369");

  script_name(english:"Unity Linux 20.1070e Security Update: kernel (UTSA-2026-005499)");

  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-2026-005499 advisory.

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

    net: dcb: choose correct policy to parse DCB_ATTR_BCN

    The dcbnl_bcn_setcfg uses erroneous policy to parse tb[DCB_ATTR_BCN],
    which is introduced in commit 859ee3c43812 (DCB: Add support for DCB
    BCN). Please see the comment in below code

    static int dcbnl_bcn_setcfg(...)
    {
      ...
      ret = nla_parse_nested_deprecated(..., dcbnl_pfc_up_nest, .. )
      // !!! dcbnl_pfc_up_nest for attributes
      //  DCB_PFC_UP_ATTR_0 to DCB_PFC_UP_ATTR_ALL in enum dcbnl_pfc_up_attrs
      ...
      for (i = DCB_BCN_ATTR_RP_0; i <= DCB_BCN_ATTR_RP_7; i++) {
      // !!! DCB_BCN_ATTR_RP_0 to DCB_BCN_ATTR_RP_7 in enum dcbnl_bcn_attrs
        ...
        value_byte = nla_get_u8(data[i]);
        ...
      }
      ...
      for (i = DCB_BCN_ATTR_BCNA_0; i <= DCB_BCN_ATTR_RI; i++) {
      // !!! DCB_BCN_ATTR_BCNA_0 to DCB_BCN_ATTR_RI in enum dcbnl_bcn_attrs
      ...
        value_int = nla_get_u32(data[i]);
      ...
      }
      ...
    }

    That is, the nla_parse_nested_deprecated uses dcbnl_pfc_up_nest
    attributes to parse nlattr defined in dcbnl_pfc_up_attrs. But the
    following access code fetch each nlattr as dcbnl_bcn_attrs attributes.
    By looking up the associated nla_policy for dcbnl_bcn_attrs. We can find
    the beginning part of these two policies are same.

    static const struct nla_policy dcbnl_pfc_up_nest[...] = {
            [DCB_PFC_UP_ATTR_0]   = {.type = NLA_U8},
            [DCB_PFC_UP_ATTR_1]   = {.type = NLA_U8},
            [DCB_PFC_UP_ATTR_2]   = {.type = NLA_U8},
            [DCB_PFC_UP_ATTR_3]   = {.type = NLA_U8},
            [DCB_PFC_UP_ATTR_4]   = {.type = NLA_U8},
            [DCB_PFC_UP_ATTR_5]   = {.type = NLA_U8},
            [DCB_PFC_UP_ATTR_6]   = {.type = NLA_U8},
            [DCB_PFC_UP_ATTR_7]   = {.type = NLA_U8},
            [DCB_PFC_UP_ATTR_ALL] = {.type = NLA_FLAG},
    };

    static const struct nla_policy dcbnl_bcn_nest[...] = {
            [DCB_BCN_ATTR_RP_0]         = {.type = NLA_U8},
            [DCB_BCN_ATTR_RP_1]         = {.type = NLA_U8},
            [DCB_BCN_ATTR_RP_2]         = {.type = NLA_U8},
            [DCB_BCN_ATTR_RP_3]         = {.type = NLA_U8},
            [DCB_BCN_ATTR_RP_4]         = {.type = NLA_U8},
            [DCB_BCN_ATTR_RP_5]         = {.type = NLA_U8},
            [DCB_BCN_ATTR_RP_6]         = {.type = NLA_U8},
            [DCB_BCN_ATTR_RP_7]         = {.type = NLA_U8},
            [DCB_BCN_ATTR_RP_ALL]       = {.type = NLA_FLAG},
            // from here is somewhat different
            [DCB_BCN_ATTR_BCNA_0]       = {.type = NLA_U32},
            ...
            [DCB_BCN_ATTR_ALL]          = {.type = NLA_FLAG},
    };

    Therefore, the current code is buggy and this
    nla_parse_nested_deprecated could overflow the dcbnl_pfc_up_nest and use
    the adjacent nla_policy to parse attributes from DCB_BCN_ATTR_BCNA_0.

    Hence use the correct policy dcbnl_bcn_nest to parse the nested
    tb[DCB_ATTR_BCN] TLV.

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-2026-005499
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?521fb3c5");
  # https://lore.kernel.org/linux-cve-announce/2025091854-CVE-2023-53369-394e@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?e54281a7");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2023-53369");
  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-2023-53369");

  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:"2021/07/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/03/02");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/03/05");

  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:"^20.1070e([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 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': '1070e',
    'pkgs': [
      {'reference':'kernel-5.10.0-79.7', 'sp':'1070e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.7', 'sp':'1070e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.7', 'sp':'1070e', 'cpu':'sw_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.7', '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');
}