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Unity Linux 20.1070a Security Update: kernel (UTSA-2026-013065)

🗓️ 21 Apr 2026 00:00:00Reported by TenableType 
nessus
 nessus
🔗 www.tenable.com👁 17 Views

Kernel fix for cnic use-after-free; uses cancel_delayed_work_sync() to safely deallocate.

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

include('compat.inc');

if (description)
{
  script_id(307754);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/21");

  script_cve_id("CVE-2025-39945");

  script_name(english:"Unity Linux 20.1070a Security Update: kernel (UTSA-2026-013065)");

  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-2026-013065 advisory.

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

    cnic: Fix use-after-free bugs in cnic_delete_task

    The original code uses cancel_delayed_work() in cnic_cm_stop_bnx2x_hw(),
    which does not guarantee that the delayed work item 'delete_task' has
    fully completed if it was already running. Additionally, the delayed work
    item is cyclic, the flush_workqueue() in cnic_cm_stop_bnx2x_hw() only
    blocks and waits for work items that were already queued to the
    workqueue prior to its invocation. Any work items submitted after
    flush_workqueue() is called are not included in the set of tasks that the
    flush operation awaits. This means that after the cyclic work items have
    finished executing, a delayed work item may still exist in the workqueue.
    This leads to use-after-free scenarios where the cnic_dev is deallocated
    by cnic_free_dev(), while delete_task remains active and attempt to
    dereference cnic_dev in cnic_delete_task().

    A typical race condition is illustrated below:

    CPU 0 (cleanup)              | CPU 1 (delayed work callback)
    cnic_netdev_event()          |
      cnic_stop_hw()             | cnic_delete_task()
        cnic_cm_stop_bnx2x_hw()  | ...
          cancel_delayed_work()  | /* the queue_delayed_work()
          flush_workqueue()      |    executes after flush_workqueue()*/
                                 | queue_delayed_work()
      cnic_free_dev(dev)//free   | cnic_delete_task() //new instance
                                 |   dev = cp->dev; //use

    Replace cancel_delayed_work() with cancel_delayed_work_sync() to ensure
    that the cyclic delayed work item is properly canceled and that any
    ongoing execution of the work item completes before the cnic_dev is
    deallocated. Furthermore, since cancel_delayed_work_sync() uses
    __flush_work(work, true) to synchronously wait for any currently
    executing instance of the work item to finish, the flush_workqueue()
    becomes redundant and should be removed.

    This bug was identified through static analysis. To reproduce the issue
    and validate the fix, I simulated the cnic PCI device in QEMU and
    introduced intentional delays  such as inserting calls to ssleep()
    within the cnic_delete_task() function  to increase the likelihood
    of triggering the bug.

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-2026-013065
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?efb978cf");
  # https://lore.kernel.org/linux-cve-announce/2025100419-CVE-2025-39945-84d4@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?6be57792");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2025-39945");
  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-2025-39945");

  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:"2025/10/04");
  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');
}

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21 Apr 2026 00:00Current
6.9Medium risk
Vulners AI Score6.9
CVSS 3.17.8
EPSS0.00148
SSVC
17