Unity Linux 20.1050a Security Update: kernel (UTSA-2026-098833)

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

include('compat.inc');

if (description)
{
  script_id(340178);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/26");

  script_cve_id("CVE-2026-23378");

  script_name(english:"Unity Linux 20.1050a Security Update: kernel (UTSA-2026-098833)");

  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-2026-098833 advisory.

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

    net/sched: act_ife: Fix metalist update behavior

    Whenever an ife action replace changes the metalist, instead of
    replacing the old data on the metalist, the current ife code is appending
    the new metadata. Aside from being innapropriate behavior, this may lead
    to an unbounded addition of metadata to the metalist which might cause an
    out of bounds error when running the encode op:

    [  138.423369][    C1] ==================================================================
    [  138.424317][    C1] BUG: KASAN: slab-out-of-bounds in ife_tlv_meta_encode (net/ife/ife.c:168)
    [  138.424906][    C1] Write of size 4 at addr ffff8880077f4ffe by task ife_out_out_bou/255
    [  138.425778][    C1] CPU: 1 UID: 0 PID: 255 Comm: ife_out_out_bou Not tainted
    7.0.0-rc1-00169-gfbdfa8da05b6 #624 PREEMPT(full)
    [  138.425795][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
    [  138.425800][    C1] Call Trace:
    [  138.425804][    C1]  <IRQ>
    [  138.425808][    C1]  dump_stack_lvl (lib/dump_stack.c:122)
    [  138.425828][    C1]  print_report (mm/kasan/report.c:379 mm/kasan/report.c:482)
    [  138.425839][    C1]  ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
    [  138.425844][    C1]  ? __virt_addr_valid (./arch/x86/include/asm/preempt.h:95 (discriminator 1)
    ./include/linux/rcupdate.h:975 (discriminator 1) ./include/linux/mmzone.h:2207 (discriminator 1)
    arch/x86/mm/physaddr.c:54 (discriminator 1))
    [  138.425853][    C1]  ? ife_tlv_meta_encode (net/ife/ife.c:168)
    [  138.425859][    C1]  kasan_report (mm/kasan/report.c:221 mm/kasan/report.c:597)
    [  138.425868][    C1]  ? ife_tlv_meta_encode (net/ife/ife.c:168)
    [  138.425878][    C1]  kasan_check_range (mm/kasan/generic.c:186 (discriminator 1) mm/kasan/generic.c:200
    (discriminator 1))
    [  138.425884][    C1]  __asan_memset (mm/kasan/shadow.c:84 (discriminator 2))
    [  138.425889][    C1]  ife_tlv_meta_encode (net/ife/ife.c:168)
    [  138.425893][    C1]  ? ife_tlv_meta_encode (net/ife/ife.c:171)
    [  138.425898][    C1]  ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
    [  138.425903][    C1]  ife_encode_meta_u16 (net/sched/act_ife.c:57)
    [  138.425910][    C1]  ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114)
    [  138.425916][    C1]  ? __asan_memcpy (mm/kasan/shadow.c:105 (discriminator 3))
    [  138.425921][    C1]  ? __pfx_ife_encode_meta_u16 (net/sched/act_ife.c:45)
    [  138.425927][    C1]  ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
    [  138.425931][    C1]  tcf_ife_act (net/sched/act_ife.c:847 net/sched/act_ife.c:879)

    To solve this issue, fix the replace behavior by adding the metalist to
    the ife rcu data structure.

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-2026-098833
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?db090600");
  # https://lore.kernel.org/linux-cve-announce/2026032542-CVE-2026-23378-f329@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?a33d8c14");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2026-23378");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:L/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:L/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-2026-23378");

  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:"2026/03/25");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/08/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/26");

  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([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 20.1050a', '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 && 'loongarch64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1050a',
    'pkgs': [
      {'reference':'kernel-4.19.0-91.82.132.24.uelc20', 'sp':'1050a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.0-91.82.132.24.uelc20', 'sp':'1050a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.0-91.82.132.24.uelc20', 'sp':'1050a', 'cpu':'loongarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.0-91.82.132.24.uelc20', 'sp':'1050a', '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');
}