Unity Linux 20.1070a Security Update: kernel (UTSA-2026-013676)

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

include('compat.inc');

if (description)
{
  script_id(309587);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/22");

  script_cve_id("CVE-2023-53709");

  script_name(english:"Unity Linux 20.1070a Security Update: kernel (UTSA-2026-013676)");

  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-2026-013676 advisory.

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

    ring-buffer: Handle race between rb_move_tail and rb_check_pages

    It seems a data race between ring_buffer writing and integrity check.
    That is, RB_FLAG of head_page is been updating, while at same time
    RB_FLAG was cleared when doing integrity check rb_check_pages():

      rb_check_pages()            rb_handle_head_page():
      --------                    --------
      rb_head_page_deactivate()
                                  rb_head_page_set_normal()
      rb_head_page_activate()

    We do intergrity test of the list to check if the list is corrupted and
    it is still worth doing it. So, let's refactor rb_check_pages() such that
    we no longer clear and set flag during the list sanity checking.

    [1] and [2] are the test to reproduce and the crash report respectively.

    1:
    ``` read_trace.sh
      while true;
      do
        # the trace file is closed after read
        head -1 /sys/kernel/tracing/trace > /dev/null
      done
    ```
    ``` repro.sh
      sysctl -w kernel.panic_on_warn=1
      # function tracer will writing enough data into ring_buffer
      echo function > /sys/kernel/tracing/current_tracer
      ./read_trace.sh &
      ./read_trace.sh &
      ./read_trace.sh &
      ./read_trace.sh &
      ./read_trace.sh &
      ./read_trace.sh &
      ./read_trace.sh &
      ./read_trace.sh &
    ```

    2:
    ------------[ cut here ]------------
    WARNING: CPU: 9 PID: 62 at kernel/trace/ring_buffer.c:2653
    rb_move_tail+0x450/0x470
    Modules linked in:
    CPU: 9 PID: 62 Comm: ksoftirqd/9 Tainted: G        W          6.2.0-rc6+
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
    rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
    RIP: 0010:rb_move_tail+0x450/0x470
    Code: ff ff 4c 89 c8 f0 4d 0f b1 02 48 89 c2 48 83 e2 fc 49 39 d0 75 24
    83 e0 03 83 f8 02 0f 84 e1 fb ff ff 48 8b 57 10 f0 ff 42 08 <0f> 0b 83
    f8 02 0f 84 ce fb ff ff e9 db
    RSP: 0018:ffffb5564089bd00 EFLAGS: 00000203
    RAX: 0000000000000000 RBX: ffff9db385a2bf81 RCX: ffffb5564089bd18
    RDX: ffff9db281110100 RSI: 0000000000000fe4 RDI: ffff9db380145400
    RBP: ffff9db385a2bf80 R08: ffff9db385a2bfc0 R09: ffff9db385a2bfc2
    R10: ffff9db385a6c000 R11: ffff9db385a2bf80 R12: 0000000000000000
    R13: 00000000000003e8 R14: ffff9db281110100 R15: ffffffffbb006108
    FS:  0000000000000000(0000) GS:ffff9db3bdcc0000(0000)
    knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 00005602323024c8 CR3: 0000000022e0c000 CR4: 00000000000006e0
    Call Trace:
     <TASK>
     ring_buffer_lock_reserve+0x136/0x360
     ? __do_softirq+0x287/0x2df
     ? __pfx_rcu_softirq_qs+0x10/0x10
     trace_function+0x21/0x110
     ? __pfx_rcu_softirq_qs+0x10/0x10
     ? __do_softirq+0x287/0x2df
     function_trace_call+0xf6/0x120
     0xffffffffc038f097
     ? rcu_softirq_qs+0x5/0x140
     rcu_softirq_qs+0x5/0x140
     __do_softirq+0x287/0x2df
     run_ksoftirqd+0x2a/0x30
     smpboot_thread_fn+0x188/0x220
     ? __pfx_smpboot_thread_fn+0x10/0x10
     kthread+0xe7/0x110
     ? __pfx_kthread+0x10/0x10
     ret_from_fork+0x2c/0x50
     </TASK>
    ---[ end trace 0000000000000000 ]---

    [ crash report and test reproducer credit goes to Zheng Yejian]

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-2026-013676
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?558160d6");
  # https://lore.kernel.org/linux-cve-announce/2025102212-CVE-2023-53709-553a@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?34c9284f");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2023-53709");
  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-2023-53709");

  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:"2026/04/22");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/22");

  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:"^20.1070a([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 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 && 'loongarch64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1070a',
    'pkgs': [
      {'reference':'kernel-5.10.0-38', 'sp':'1070a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-38', 'sp':'1070a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-38', 'sp':'1070a', 'cpu':'loongarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-38', 'sp':'1070a', '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');
}