Unity Linux 20.1050e / 20.1060e / 20.1070e Security Update: kernel (UTSA-2026-010836)

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

include('compat.inc');

if (description)
{
  script_id(308878);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/22");

  script_cve_id("CVE-2025-40042");

  script_name(english:"Unity Linux 20.1050e / 20.1060e / 20.1070e Security Update: kernel (UTSA-2026-010836)");

  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-2026-010836 advisory.

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

    tracing: Fix race condition in kprobe initialization causing NULL pointer dereference

    There is a critical race condition in kprobe initialization that can lead to
    NULL pointer dereference and kernel crash.

    [1135630.084782] Unable to handle kernel paging request at virtual address 0000710a04630000
    ...
    [1135630.260314] pstate: 404003c9 (nZcv DAIF +PAN -UAO)
    [1135630.269239] pc : kprobe_perf_func+0x30/0x260
    [1135630.277643] lr : kprobe_dispatcher+0x44/0x60
    [1135630.286041] sp : ffffaeff4977fa40
    [1135630.293441] x29: ffffaeff4977fa40 x28: ffffaf015340e400
    [1135630.302837] x27: 0000000000000000 x26: 0000000000000000
    [1135630.312257] x25: ffffaf029ed108a8 x24: ffffaf015340e528
    [1135630.321705] x23: ffffaeff4977fc50 x22: ffffaeff4977fc50
    [1135630.331154] x21: 0000000000000000 x20: ffffaeff4977fc50
    [1135630.340586] x19: ffffaf015340e400 x18: 0000000000000000
    [1135630.349985] x17: 0000000000000000 x16: 0000000000000000
    [1135630.359285] x15: 0000000000000000 x14: 0000000000000000
    [1135630.368445] x13: 0000000000000000 x12: 0000000000000000
    [1135630.377473] x11: 0000000000000000 x10: 0000000000000000
    [1135630.386411] x9 : 0000000000000000 x8 : 0000000000000000
    [1135630.395252] x7 : 0000000000000000 x6 : 0000000000000000
    [1135630.403963] x5 : 0000000000000000 x4 : 0000000000000000
    [1135630.412545] x3 : 0000710a04630000 x2 : 0000000000000006
    [1135630.421021] x1 : ffffaeff4977fc50 x0 : 0000710a04630000
    [1135630.429410] Call trace:
    [1135630.434828]  kprobe_perf_func+0x30/0x260
    [1135630.441661]  kprobe_dispatcher+0x44/0x60
    [1135630.448396]  aggr_pre_handler+0x70/0xc8
    [1135630.454959]  kprobe_breakpoint_handler+0x140/0x1e0
    [1135630.462435]  brk_handler+0xbc/0xd8
    [1135630.468437]  do_debug_exception+0x84/0x138
    [1135630.475074]  el1_dbg+0x18/0x8c
    [1135630.480582]  security_file_permission+0x0/0xd0
    [1135630.487426]  vfs_write+0x70/0x1c0
    [1135630.493059]  ksys_write+0x5c/0xc8
    [1135630.498638]  __arm64_sys_write+0x24/0x30
    [1135630.504821]  el0_svc_common+0x78/0x130
    [1135630.510838]  el0_svc_handler+0x38/0x78
    [1135630.516834]  el0_svc+0x8/0x1b0

    kernel/trace/trace_kprobe.c: 1308
    0xffff3df8995039ec <kprobe_perf_func+0x2c>:     ldr     x21, [x24,#120]
    include/linux/compiler.h: 294
    0xffff3df8995039f0 <kprobe_perf_func+0x30>:     ldr     x1, [x21,x0]

    kernel/trace/trace_kprobe.c
    1308: head = this_cpu_ptr(call->perf_events);
    1309: if (hlist_empty(head))
    1310:   return 0;

    crash> struct trace_event_call -o
    struct trace_event_call {
      ...
      [120] struct hlist_head *perf_events;  //(call->perf_event)
      ...
    }

    crash> struct trace_event_call ffffaf015340e528
    struct trace_event_call {
      ...
      perf_events = 0xffff0ad5fa89f088, //this value is correct, but x21 = 0
      ...
    }

    Race Condition Analysis:

    The race occurs between kprobe activation and perf_events initialization:

      CPU0                                    CPU1
      ====                                    ====
      perf_kprobe_init
        perf_trace_event_init
          tp_event->perf_events = list;(1)
          tp_event->class->reg (2) KPROBE ACTIVE
                                              Debug exception triggers
                                              ...
                                              kprobe_dispatcher
                                                kprobe_perf_func (tk->tp.flags & TP_FLAG_PROFILE)
                                                  head = this_cpu_ptr(call->perf_events)(3)
                                                  (perf_events is still NULL)

    Problem:
    1. CPU0 executes (1) assigning tp_event->perf_events = list
    2. CPU0 executes (2) enabling kprobe functionality via class->reg()
    3. CPU1 triggers and reaches kprobe_dispatcher
    4. CPU1 checks TP_FLAG_PROFILE - condition passes (step 2 completed)
    5. CPU1 calls kprobe_perf_func() and crashes at (3) because
       call->perf_events is still NULL

    CPU1 sees that kprobe functionality is enabled but does not see that
    perf_events has been assigned.

    Add pairing read an
    ---truncated---

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-2026-010836
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?2dd78ca1");
  # https://lore.kernel.org/linux-cve-announce/2025102812-CVE-2025-40042-80e6@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?15aac8fa");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2025-40042");
  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-2025-40042");

  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:"2025/10/23");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/04/20");
  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:"^20.1050e|20.1060e|20.1070e([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 20.1050e / 20.1060e / 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': '1050e',
    'pkgs': [
      {'reference':'kernel-5.10.0-27.5', 'sp':'1050e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-27.5', 'sp':'1050e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-27.5', 'sp':'1050e', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  },
  {
    'release': '20',
    'sp': '1060e',
    'pkgs': [
      {'reference':'kernel-5.10.0-46.38', 'sp':'1060e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-46.38', 'sp':'1060e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-46.38', 'sp':'1060e', 'cpu':'sw_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-46.38', 'sp':'1060e', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  },
  {
    'release': '20',
    'sp': '1070e',
    'pkgs': [
      {'reference':'kernel-5.10.0-79.5', 'sp':'1070e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.5', 'sp':'1070e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.5', 'sp':'1070e', 'cpu':'sw_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.5', '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');
}