Unity Linux 20.1050e Security Update: kernel (UTSA-2026-004841)

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

include('compat.inc');

if (description)
{
  script_id(296353);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/01/23");

  script_cve_id("CVE-2022-50408");

  script_name(english:"Unity Linux 20.1050e Security Update: kernel (UTSA-2026-004841)");

  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-2026-004841 advisory.

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

    wifi: brcmfmac: fix use-after-free bug in brcmf_netdev_start_xmit()

    > ret = brcmf_proto_tx_queue_data(drvr, ifp->ifidx, skb);

    may be schedule, and then complete before the line

    > ndev->stats.tx_bytes += skb->len;

    [   46.912801] ==================================================================
    [   46.920552] BUG: KASAN: use-after-free in brcmf_netdev_start_xmit+0x718/0x8c8 [brcmfmac]
    [   46.928673] Read of size 4 at addr ffffff803f5882e8 by task systemd-resolve/328
    [   46.935991]
    [   46.937514] CPU: 1 PID: 328 Comm: systemd-resolve Tainted: G           O      5.4.199-[REDACTED] #1
    [   46.947255] Hardware name: [REDACTED]
    [   46.954568] Call trace:
    [   46.957037]  dump_backtrace+0x0/0x2b8
    [   46.960719]  show_stack+0x24/0x30
    [   46.964052]  dump_stack+0x128/0x194
    [   46.967557]  print_address_description.isra.0+0x64/0x380
    [   46.972877]  __kasan_report+0x1d4/0x240
    [   46.976723]  kasan_report+0xc/0x18
    [   46.980138]  __asan_report_load4_noabort+0x18/0x20
    [   46.985027]  brcmf_netdev_start_xmit+0x718/0x8c8 [brcmfmac]
    [   46.990613]  dev_hard_start_xmit+0x1bc/0xda0
    [   46.994894]  sch_direct_xmit+0x198/0xd08
    [   46.998827]  __qdisc_run+0x37c/0x1dc0
    [   47.002500]  __dev_queue_xmit+0x1528/0x21f8
    [   47.006692]  dev_queue_xmit+0x24/0x30
    [   47.010366]  neigh_resolve_output+0x37c/0x678
    [   47.014734]  ip_finish_output2+0x598/0x2458
    [   47.018927]  __ip_finish_output+0x300/0x730
    [   47.023118]  ip_output+0x2e0/0x430
    [   47.026530]  ip_local_out+0x90/0x140
    [   47.030117]  igmpv3_sendpack+0x14c/0x228
    [   47.034049]  igmpv3_send_cr+0x384/0x6b8
    [   47.037895]  igmp_ifc_timer_expire+0x4c/0x118
    [   47.042262]  call_timer_fn+0x1cc/0xbe8
    [   47.046021]  __run_timers+0x4d8/0xb28
    [   47.049693]  run_timer_softirq+0x24/0x40
    [   47.053626]  __do_softirq+0x2c0/0x117c
    [   47.057387]  irq_exit+0x2dc/0x388
    [   47.060715]  __handle_domain_irq+0xb4/0x158
    [   47.064908]  gic_handle_irq+0x58/0xb0
    [   47.068581]  el0_irq_naked+0x50/0x5c
    [   47.072162]
    [   47.073665] Allocated by task 328:
    [   47.077083]  save_stack+0x24/0xb0
    [   47.080410]  __kasan_kmalloc.isra.0+0xc0/0xe0
    [   47.084776]  kasan_slab_alloc+0x14/0x20
    [   47.088622]  kmem_cache_alloc+0x15c/0x468
    [   47.092643]  __alloc_skb+0xa4/0x498
    [   47.096142]  igmpv3_newpack+0x158/0xd78
    [   47.099987]  add_grhead+0x210/0x288
    [   47.103485]  add_grec+0x6b0/0xb70
    [   47.106811]  igmpv3_send_cr+0x2e0/0x6b8
    [   47.110657]  igmp_ifc_timer_expire+0x4c/0x118
    [   47.115027]  call_timer_fn+0x1cc/0xbe8
    [   47.118785]  __run_timers+0x4d8/0xb28
    [   47.122457]  run_timer_softirq+0x24/0x40
    [   47.126389]  __do_softirq+0x2c0/0x117c
    [   47.130142]
    [   47.131643] Freed by task 180:
    [   47.134712]  save_stack+0x24/0xb0
    [   47.138041]  __kasan_slab_free+0x108/0x180
    [   47.142146]  kasan_slab_free+0x10/0x18
    [   47.145904]  slab_free_freelist_hook+0xa4/0x1b0
    [   47.150444]  kmem_cache_free+0x8c/0x528
    [   47.154292]  kfree_skbmem+0x94/0x108
    [   47.157880]  consume_skb+0x10c/0x5a8
    [   47.161466]  __dev_kfree_skb_any+0x88/0xa0
    [   47.165598]  brcmu_pkt_buf_free_skb+0x44/0x68 [brcmutil]
    [   47.171023]  brcmf_txfinalize+0xec/0x190 [brcmfmac]
    [   47.176016]  brcmf_proto_bcdc_txcomplete+0x1c0/0x210 [brcmfmac]
    [   47.182056]  brcmf_sdio_sendfromq+0x8dc/0x1e80 [brcmfmac]
    [   47.187568]  brcmf_sdio_dpc+0xb48/0x2108 [brcmfmac]
    [   47.192529]  brcmf_sdio_dataworker+0xc8/0x238 [brcmfmac]
    [   47.197859]  process_one_work+0x7fc/0x1a80
    [   47.201965]  worker_thread+0x31c/0xc40
    [   47.205726]  kthread+0x2d8/0x370
    [   47.208967]  ret_from_fork+0x10/0x18
    [   47.212546]
    [   47.214051] The buggy address belongs to the object at ffffff803f588280
    [   47.214051]  which belongs to the cache skbuff_head_cache of size 208
    [   47.227086] The buggy address is located 104 bytes inside of
    [   47.227086]  208-byte region [ffffff803f588280, ffffff803f588350)
    [   47.238814] The buggy address belongs to the page:
    [   47.243618] page:ffffffff00dd6200 refcount:1 mapcou
    ---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-2026-004841
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?a88c8ad9");
  # https://lore.kernel.org/linux-cve-announce/2025091853-CVE-2022-50408-5835@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?a7f4861b");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2022-50408");
  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-2022-50408");

  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:"2021/09/04");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/01/23");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/01/23");

  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([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 20.1050e', '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': '1050e',
    'pkgs': [
      {'reference':'kernel-4.19.90-2211.5.0.0178.47', 'sp':'1050e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.5.0.0178.47', 'sp':'1050e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.5.0.0178.47', 'sp':'1050e', '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');
}