Unity Linux 20.1050a Security Update: kernel (UTSA-2026-100359)

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

include('compat.inc');

if (description)
{
  script_id(336634);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/17");

  script_cve_id("CVE-2023-54094");

  script_name(english:"Unity Linux 20.1050a Security Update: kernel (UTSA-2026-100359)");

  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-2026-100359 advisory.

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

    net: prevent skb corruption on frag list segmentation

    Ian reported several skb corruptions triggered by rx-gro-list,
    collecting different oops alike:

    [   62.624003] BUG: kernel NULL pointer dereference, address: 00000000000000c0
    [   62.631083] #PF: supervisor read access in kernel mode
    [   62.636312] #PF: error_code(0x0000) - not-present page
    [   62.641541] PGD 0 P4D 0
    [   62.644174] Oops: 0000 [#1] PREEMPT SMP NOPTI
    [   62.648629] CPU: 1 PID: 913 Comm: napi/eno2-79 Not tainted 6.4.0 #364
    [   62.655162] Hardware name: Supermicro Super Server/A2SDi-12C-HLN4F, BIOS 1.7a 10/13/2022
    [   62.663344] RIP: 0010:__udp_gso_segment (./include/linux/skbuff.h:2858
    ./include/linux/udp.h:23 net/ipv4/udp_offload.c:228 net/ipv4/udp_offload.c:261
    net/ipv4/udp_offload.c:277)
    [   62.687193] RSP: 0018:ffffbd3a83b4f868 EFLAGS: 00010246
    [   62.692515] RAX: 00000000000000ce RBX: 0000000000000000 RCX: 0000000000000000
    [   62.699743] RDX: ffffa124def8a000 RSI: 0000000000000079 RDI: ffffa125952a14d4
    [   62.706970] RBP: ffffa124def8a000 R08: 0000000000000022 R09: 00002000001558c9
    [   62.714199] R10: 0000000000000000 R11: 00000000be554639 R12: 00000000000000e2
    [   62.721426] R13: ffffa125952a1400 R14: ffffa125952a1400 R15: 00002000001558c9
    [   62.728654] FS:  0000000000000000(0000) GS:ffffa127efa40000(0000)
    knlGS:0000000000000000
    [   62.736852] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    [   62.742702] CR2: 00000000000000c0 CR3: 00000001034b0000 CR4: 00000000003526e0
    [   62.749948] Call Trace:
    [   62.752498]  <TASK>
    [   62.779267] inet_gso_segment (net/ipv4/af_inet.c:1398)
    [   62.787605] skb_mac_gso_segment (net/core/gro.c:141)
    [   62.791906] __skb_gso_segment (net/core/dev.c:3403 (discriminator 2))
    [   62.800492] validate_xmit_skb (./include/linux/netdevice.h:4862
    net/core/dev.c:3659)
    [   62.804695] validate_xmit_skb_list (net/core/dev.c:3710)
    [   62.809158] sch_direct_xmit (net/sched/sch_generic.c:330)
    [   62.813198] __dev_queue_xmit (net/core/dev.c:3805 net/core/dev.c:4210)
    net/netfilter/core.c:626)
    [   62.821093] br_dev_queue_push_xmit (net/bridge/br_forward.c:55)
    [   62.825652] maybe_deliver (net/bridge/br_forward.c:193)
    [   62.829420] br_flood (net/bridge/br_forward.c:233)
    [   62.832758] br_handle_frame_finish (net/bridge/br_input.c:215)
    [   62.837403] br_handle_frame (net/bridge/br_input.c:298
    net/bridge/br_input.c:416)
    [   62.851417] __netif_receive_skb_core.constprop.0 (net/core/dev.c:5387)
    [   62.866114] __netif_receive_skb_list_core (net/core/dev.c:5570)
    [   62.871367] netif_receive_skb_list_internal (net/core/dev.c:5638
    net/core/dev.c:5727)
    [   62.876795] napi_complete_done (./include/linux/list.h:37
    ./include/net/gro.h:434 ./include/net/gro.h:429 net/core/dev.c:6067)
    [   62.881004] ixgbe_poll (drivers/net/ethernet/intel/ixgbe/ixgbe_main.c:3191)
    [   62.893534] __napi_poll (net/core/dev.c:6498)
    [   62.897133] napi_threaded_poll (./include/linux/netpoll.h:89
    net/core/dev.c:6640)
    [   62.905276] kthread (kernel/kthread.c:379)
    [   62.913435] ret_from_fork (arch/x86/entry/entry_64.S:314)
    [   62.917119]  </TASK>

    In the critical scenario, rx-gro-list GRO-ed packets are fed, via a
    bridge, both to the local input path and to an egress device (tun).

    The segmentation of such packets unsafely writes to the cloned skbs
    with shared heads.

    This change addresses the issue by uncloning as needed the
    to-be-segmented skbs.

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-2026-100359
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?fb392ef7");
  # https://lore.kernel.org/linux-cve-announce/2025122408-CVE-2023-54094-e8ce@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?72354553");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2023-54094");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/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:N/AC:L/PR:N/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-2023-54094");

  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:"2026/08/13");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/17");

  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:"^20.1050a([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 20.1050a', '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': '1050a',
    'pkgs': [
      {'reference':'kernel-5.10.0-27.18.uelc20', 'sp':'1050a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-27.18.uelc20', 'sp':'1050a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-27.18.uelc20', 'sp':'1050a', '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_HOLE,
      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');
}