Unity Linux 20.1060e / 20.1070e Security Update: kernel (UTSA-2026-013199)

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

include('compat.inc');

if (description)
{
  script_id(308134);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/21");

  script_cve_id("CVE-2022-50432");

  script_name(english:"Unity Linux 20.1060e / 20.1070e Security Update: kernel (UTSA-2026-013199)");

  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-2026-013199 advisory.

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

    kernfs: fix use-after-free in __kernfs_remove

    Syzkaller managed to trigger concurrent calls to
    kernfs_remove_by_name_ns() for the same file resulting in
    a KASAN detected use-after-free. The race occurs when the root
    node is freed during kernfs_drain().

    To prevent this acquire an additional reference for the root
    of the tree that is removed before calling __kernfs_remove().

    Found by syzkaller with the following reproducer (slab_nomerge is
    required):

    syz_mount_image$ext4(0x0, &(0x7f0000000100)='./file0\x00', 0x100000, 0x0, 0x0, 0x0, 0x0)
    r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='/proc/self/exe\x00', 0x0, 0x0)
    close(r0)
    pipe2(&(0x7f0000000140)={0xffffffffffffffff, <r1=>0xffffffffffffffff}, 0x800)
    mount$9p_fd(0x0, &(0x7f0000000040)='./file0\x00', &(0x7f00000000c0), 0x408,
    &(0x7f0000000280)={'trans=fd,', {'rfdno', 0x3d, r0}, 0x2c, {'wfdno', 0x3d, r1}, 0x2c, {[{@cache_loose},
    {@mmap}, {@loose}, {@loose}, {@mmap}], [{@mask={'mask', 0x3d, '^MAY_EXEC'}}, {@fsmagic={'fsmagic', 0x3d,
    0x10001}}, {@dont_hash}]}})

    Sample report:

    ==================================================================
    BUG: KASAN: use-after-free in kernfs_type include/linux/kernfs.h:335 [inline]
    BUG: KASAN: use-after-free in kernfs_leftmost_descendant fs/kernfs/dir.c:1261 [inline]
    BUG: KASAN: use-after-free in __kernfs_remove.part.0+0x843/0x960 fs/kernfs/dir.c:1369
    Read of size 2 at addr ffff8880088807f0 by task syz-executor.2/857

    CPU: 0 PID: 857 Comm: syz-executor.2 Not tainted 6.0.0-rc3-00363-g7726d4c3e60b #5
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
    Call Trace:
     <TASK>
     __dump_stack lib/dump_stack.c:88 [inline]
     dump_stack_lvl+0x6e/0x91 lib/dump_stack.c:106
     print_address_description mm/kasan/report.c:317 [inline]
     print_report.cold+0x5e/0x5e5 mm/kasan/report.c:433
     kasan_report+0xa3/0x130 mm/kasan/report.c:495
     kernfs_type include/linux/kernfs.h:335 [inline]
     kernfs_leftmost_descendant fs/kernfs/dir.c:1261 [inline]
     __kernfs_remove.part.0+0x843/0x960 fs/kernfs/dir.c:1369
     __kernfs_remove fs/kernfs/dir.c:1356 [inline]
     kernfs_remove_by_name_ns+0x108/0x190 fs/kernfs/dir.c:1589
     sysfs_slab_add+0x133/0x1e0 mm/slub.c:5943
     __kmem_cache_create+0x3e0/0x550 mm/slub.c:4899
     create_cache mm/slab_common.c:229 [inline]
     kmem_cache_create_usercopy+0x167/0x2a0 mm/slab_common.c:335
     p9_client_create+0xd4d/0x1190 net/9p/client.c:993
     v9fs_session_init+0x1e6/0x13c0 fs/9p/v9fs.c:408
     v9fs_mount+0xb9/0xbd0 fs/9p/vfs_super.c:126
     legacy_get_tree+0xf1/0x200 fs/fs_context.c:610
     vfs_get_tree+0x85/0x2e0 fs/super.c:1530
     do_new_mount fs/namespace.c:3040 [inline]
     path_mount+0x675/0x1d00 fs/namespace.c:3370
     do_mount fs/namespace.c:3383 [inline]
     __do_sys_mount fs/namespace.c:3591 [inline]
     __se_sys_mount fs/namespace.c:3568 [inline]
     __x64_sys_mount+0x282/0x300 fs/namespace.c:3568
     do_syscall_x64 arch/x86/entry/common.c:50 [inline]
     do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80
     entry_SYSCALL_64_after_hwframe+0x63/0xcd
    RIP: 0033:0x7f725f983aed
    Code: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d
    89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
    RSP: 002b:00007f725f0f7028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
    RAX: ffffffffffffffda RBX: 00007f725faa3f80 RCX: 00007f725f983aed
    RDX: 00000000200000c0 RSI: 0000000020000040 RDI: 0000000000000000
    RBP: 00007f725f9f419c R08: 0000000020000280 R09: 0000000000000000
    R10: 0000000000000408 R11: 0000000000000246 R12: 0000000000000000
    R13: 0000000000000006 R14: 00007f725faa3f80 R15: 00007f725f0d7000
     </TASK>

    Allocated by task 855:
     kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
     kasan_set_track mm/kasan/common.c:45 [inline]
     set_alloc_info mm/kasan/common.c:437 [inline]
     __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:470
     kasan_slab_alloc include/linux/kasan.h:224 [inline]
     slab_post_alloc_hook mm/slab.h:7
    ---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-2026-013199
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?cd6d76a9");
  # https://lore.kernel.org/linux-cve-announce/2025100158-CVE-2022-50432-bb35@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?ca669882");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2022-50432");
  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-2022-50432");

  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:"2026/04/21");
  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:"^20.1060e|20.1070e([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 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': '1060e',
    'pkgs': [
      {'reference':'kernel-4.19.90-2212.2.0', 'sp':'1060e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2212.2.0', 'sp':'1060e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2212.2.0', 'sp':'1060e', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  },
  {
    'release': '20',
    'sp': '1070e',
    'pkgs': [
      {'reference':'kernel-4.19.90-2212.2.0', 'sp':'1070e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2212.2.0', 'sp':'1070e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2212.2.0', 'sp':'1070e', 'cpu':'sw_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2212.2.0', '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');
}