Unity Linux 20.1050e Security Update: kernel (UTSA-2026-021616)

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

include('compat.inc');

if (description)
{
  script_id(315900);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/20");

  script_cve_id("CVE-2024-53168");

  script_name(english:"Unity Linux 20.1050e Security Update: kernel (UTSA-2026-021616)");

  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-2026-021616 advisory.

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

    sunrpc: fix one UAF issue caused by sunrpc kernel tcp socket

    BUG: KASAN: slab-use-after-free in tcp_write_timer_handler+0x156/0x3e0
    Read of size 1 at addr ffff888111f322cd by task swapper/0/0

    CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.0-rc4-dirty #7
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1
    Call Trace:
     <IRQ>
     dump_stack_lvl+0x68/0xa0
     print_address_description.constprop.0+0x2c/0x3d0
     print_report+0xb4/0x270
     kasan_report+0xbd/0xf0
     tcp_write_timer_handler+0x156/0x3e0
     tcp_write_timer+0x66/0x170
     call_timer_fn+0xfb/0x1d0
     __run_timers+0x3f8/0x480
     run_timer_softirq+0x9b/0x100
     handle_softirqs+0x153/0x390
     __irq_exit_rcu+0x103/0x120
     irq_exit_rcu+0xe/0x20
     sysvec_apic_timer_interrupt+0x76/0x90
     </IRQ>
     <TASK>
     asm_sysvec_apic_timer_interrupt+0x1a/0x20
    RIP: 0010:default_idle+0xf/0x20
    Code: 4c 01 c7 4c 29 c2 e9 72 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90
     90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 33 f8 25 00 fb f4 <fa> c3 cc cc cc
     cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90
    RSP: 0018:ffffffffa2007e28 EFLAGS: 00000242
    RAX: 00000000000f3b31 RBX: 1ffffffff4400fc7 RCX: ffffffffa09c3196
    RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9f00590f
    RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed102360835d
    R10: ffff88811b041aeb R11: 0000000000000001 R12: 0000000000000000
    R13: ffffffffa202d7c0 R14: 0000000000000000 R15: 00000000000147d0
     default_idle_call+0x6b/0xa0
     cpuidle_idle_call+0x1af/0x1f0
     do_idle+0xbc/0x130
     cpu_startup_entry+0x33/0x40
     rest_init+0x11f/0x210
     start_kernel+0x39a/0x420
     x86_64_start_reservations+0x18/0x30
     x86_64_start_kernel+0x97/0xa0
     common_startup_64+0x13e/0x141
     </TASK>

    Allocated by task 595:
     kasan_save_stack+0x24/0x50
     kasan_save_track+0x14/0x30
     __kasan_slab_alloc+0x87/0x90
     kmem_cache_alloc_noprof+0x12b/0x3f0
     copy_net_ns+0x94/0x380
     create_new_namespaces+0x24c/0x500
     unshare_nsproxy_namespaces+0x75/0xf0
     ksys_unshare+0x24e/0x4f0
     __x64_sys_unshare+0x1f/0x30
     do_syscall_64+0x70/0x180
     entry_SYSCALL_64_after_hwframe+0x76/0x7e

    Freed by task 100:
     kasan_save_stack+0x24/0x50
     kasan_save_track+0x14/0x30
     kasan_save_free_info+0x3b/0x60
     __kasan_slab_free+0x54/0x70
     kmem_cache_free+0x156/0x5d0
     cleanup_net+0x5d3/0x670
     process_one_work+0x776/0xa90
     worker_thread+0x2e2/0x560
     kthread+0x1a8/0x1f0
     ret_from_fork+0x34/0x60
     ret_from_fork_asm+0x1a/0x30

    Reproduction script:

    mkdir -p /mnt/nfsshare
    mkdir -p /mnt/nfs/netns_1
    mkfs.ext4 /dev/sdb
    mount /dev/sdb /mnt/nfsshare
    systemctl restart nfs-server
    chmod 777 /mnt/nfsshare
    exportfs -i -o rw,no_root_squash *:/mnt/nfsshare

    ip netns add netns_1
    ip link add name veth_1_peer type veth peer veth_1
    ifconfig veth_1_peer 11.11.0.254 up
    ip link set veth_1 netns netns_1
    ip netns exec netns_1 ifconfig veth_1 11.11.0.1

    ip netns exec netns_1 /root/iptables -A OUTPUT -d 11.11.0.254 -p tcp \
            --tcp-flags FIN FIN  -j DROP

    (note: In my environment, a DESTROY_CLIENTID operation is always sent
     immediately, breaking the nfs tcp connection.)
    ip netns exec netns_1 timeout -s 9 300 mount -t nfs -o proto=tcp,vers=4.1 \
            11.11.0.254:/mnt/nfsshare /mnt/nfs/netns_1

    ip netns del netns_1

    The reason here is that the tcp socket in netns_1 (nfs side) has been
    shutdown and closed (done in xs_destroy), but the FIN message (with ack)
    is discarded, and the nfsd side keeps sending retransmission messages.
    As a result, when the tcp sock in netns_1 processes the received message,
    it sends the message (FIN message) in the sending queue, and the tcp timer
    is re-established. When the network namespace is deleted, the net structure
    accessed by tcp's timer handler function causes problems.

    To fix this problem, let's hold netns refcnt for the tcp kernel socket as
    done in other modules. This is an ugly hack which can easily be backported
    to earlier kernels. A proper fix which cleans up the interfaces will
    follow, but may not be so easy to backport.

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-2026-021616
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?f3b3cf23");
  # https://lore.kernel.org/linux-cve-announce/2024122715-CVE-2024-53168-dc92@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?edba531a");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2024-53168");
  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-2024-53168");

  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:"2024/12/27");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/05/21");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/05/20");

  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-4.19.90-2211.5.0.0178.56.uel20', 'sp':'1050e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.5.0.0178.56.uel20', 'sp':'1050e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.5.0.0178.56.uel20', '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');
}