Unity Linux 20.1070a Security Update: kernel (UTSA-2026-012962)

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

include('compat.inc');

if (description)
{
  script_id(307860);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/21");

  script_cve_id("CVE-2023-52572");

  script_name(english:"Unity Linux 20.1070a Security Update: kernel (UTSA-2026-012962)");

  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-2026-012962 advisory.

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

    cifs: Fix UAF in cifs_demultiplex_thread()

    There is a UAF when xfstests on cifs:

      BUG: KASAN: use-after-free in smb2_is_network_name_deleted+0x27/0x160
      Read of size 4 at addr ffff88810103fc08 by task cifsd/923

      CPU: 1 PID: 923 Comm: cifsd Not tainted 6.1.0-rc4+ #45
      ...
      Call Trace:
       <TASK>
       dump_stack_lvl+0x34/0x44
       print_report+0x171/0x472
       kasan_report+0xad/0x130
       kasan_check_range+0x145/0x1a0
       smb2_is_network_name_deleted+0x27/0x160
       cifs_demultiplex_thread.cold+0x172/0x5a4
       kthread+0x165/0x1a0
       ret_from_fork+0x1f/0x30
       </TASK>

      Allocated by task 923:
       kasan_save_stack+0x1e/0x40
       kasan_set_track+0x21/0x30
       __kasan_slab_alloc+0x54/0x60
       kmem_cache_alloc+0x147/0x320
       mempool_alloc+0xe1/0x260
       cifs_small_buf_get+0x24/0x60
       allocate_buffers+0xa1/0x1c0
       cifs_demultiplex_thread+0x199/0x10d0
       kthread+0x165/0x1a0
       ret_from_fork+0x1f/0x30

      Freed by task 921:
       kasan_save_stack+0x1e/0x40
       kasan_set_track+0x21/0x30
       kasan_save_free_info+0x2a/0x40
       ____kasan_slab_free+0x143/0x1b0
       kmem_cache_free+0xe3/0x4d0
       cifs_small_buf_release+0x29/0x90
       SMB2_negotiate+0x8b7/0x1c60
       smb2_negotiate+0x51/0x70
       cifs_negotiate_protocol+0xf0/0x160
       cifs_get_smb_ses+0x5fa/0x13c0
       mount_get_conns+0x7a/0x750
       cifs_mount+0x103/0xd00
       cifs_smb3_do_mount+0x1dd/0xcb0
       smb3_get_tree+0x1d5/0x300
       vfs_get_tree+0x41/0xf0
       path_mount+0x9b3/0xdd0
       __x64_sys_mount+0x190/0x1d0
       do_syscall_64+0x35/0x80
       entry_SYSCALL_64_after_hwframe+0x46/0xb0

    The UAF is because:

     mount(pid: 921)               | cifsd(pid: 923)
    -------------------------------|-------------------------------
                                   | cifs_demultiplex_thread
    SMB2_negotiate                 |
     cifs_send_recv                |
      compound_send_recv           |
       smb_send_rqst               |
        wait_for_response          |
         wait_event_state      [1] |
                                   |  standard_receive3
                                   |   cifs_handle_standard
                                   |    handle_mid
                                   |     mid->resp_buf = buf;  [2]
                                   |     dequeue_mid           [3]
         KILL the process      [4] |
        resp_iov[i].iov_base = buf |
     free_rsp_buf              [5] |
                                   |   is_network_name_deleted [6]
                                   |   callback

    1. After send request to server, wait the response until
        mid->mid_state != SUBMITTED;
    2. Receive response from server, and set it to mid;
    3. Set the mid state to RECEIVED;
    4. Kill the process, the mid state already RECEIVED, get 0;
    5. Handle and release the negotiate response;
    6. UAF.

    It can be easily reproduce with add some delay in [3] - [6].

    Only sync call has the problem since async call's callback is
    executed in cifsd process.

    Add an extra state to mark the mid state to READY before wakeup the
    waitter, then it can get the resp safely.

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-2026-012962
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?eceaa111");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2023-52572");
  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-2023-52572");

  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:"2023/10/24");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/04/21");
  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:"^20.1070a([^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 && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1070a',
    'pkgs': [
      {'reference':'kernel-5.10.0-79.10', 'sp':'1070a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.10', 'sp':'1070a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.10', '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');
}