Unity Linux 20.1050e / 20.1060e / 20.1070e Security Update: kernel (UTSA-2026-007516)

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

include('compat.inc');

if (description)
{
  script_id(307165);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/21");

  script_cve_id("CVE-2022-50638");

  script_name(english:"Unity Linux 20.1050e / 20.1060e / 20.1070e Security Update: kernel (UTSA-2026-007516)");

  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-2026-007516 advisory.

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

    ext4: fix bug_on in __es_tree_search caused by bad boot loader inode

    We got a issue as fllows:
    ==================================================================
     kernel BUG at fs/ext4/extents_status.c:203!
     invalid opcode: 0000 [#1] PREEMPT SMP
     CPU: 1 PID: 945 Comm: cat Not tainted 6.0.0-next-20221007-dirty #349
     RIP: 0010:ext4_es_end.isra.0+0x34/0x42
     RSP: 0018:ffffc9000143b768 EFLAGS: 00010203
     RAX: 0000000000000000 RBX: ffff8881769cd0b8 RCX: 0000000000000000
     RDX: 0000000000000000 RSI: ffffffff8fc27cf7 RDI: 00000000ffffffff
     RBP: ffff8881769cd0bc R08: 0000000000000000 R09: ffffc9000143b5f8
     R10: 0000000000000001 R11: 0000000000000001 R12: ffff8881769cd0a0
     R13: ffff8881768e5668 R14: 00000000768e52f0 R15: 0000000000000000
     FS: 00007f359f7f05c0(0000)GS:ffff88842fd00000(0000)knlGS:0000000000000000
     CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
     CR2: 00007f359f5a2000 CR3: 000000017130c000 CR4: 00000000000006e0
     DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
     DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
     Call Trace:
      <TASK>
      __es_tree_search.isra.0+0x6d/0xf5
      ext4_es_cache_extent+0xfa/0x230
      ext4_cache_extents+0xd2/0x110
      ext4_find_extent+0x5d5/0x8c0
      ext4_ext_map_blocks+0x9c/0x1d30
      ext4_map_blocks+0x431/0xa50
      ext4_mpage_readpages+0x48e/0xe40
      ext4_readahead+0x47/0x50
      read_pages+0x82/0x530
      page_cache_ra_unbounded+0x199/0x2a0
      do_page_cache_ra+0x47/0x70
      page_cache_ra_order+0x242/0x400
      ondemand_readahead+0x1e8/0x4b0
      page_cache_sync_ra+0xf4/0x110
      filemap_get_pages+0x131/0xb20
      filemap_read+0xda/0x4b0
      generic_file_read_iter+0x13a/0x250
      ext4_file_read_iter+0x59/0x1d0
      vfs_read+0x28f/0x460
      ksys_read+0x73/0x160
      __x64_sys_read+0x1e/0x30
      do_syscall_64+0x35/0x80
      entry_SYSCALL_64_after_hwframe+0x63/0xcd
      </TASK>
    ==================================================================

    In the above issue, ioctl invokes the swap_inode_boot_loader function to
    swap inode<5> and inode<12>. However, inode<5> contain incorrect imode and
    disordered extents, and i_nlink is set to 1. The extents check for inode in
    the ext4_iget function can be bypassed bacause 5 is EXT4_BOOT_LOADER_INO.
    While links_count is set to 1, the extents are not initialized in
    swap_inode_boot_loader. After the ioctl command is executed successfully,
    the extents are swapped to inode<12>, in this case, run the `cat` command
    to view inode<12>. And Bug_ON is triggered due to the incorrect extents.

    When the boot loader inode is not initialized, its imode can be one of the
    following:
    1) the imode is a bad type, which is marked as bad_inode in ext4_iget and
       set to S_IFREG.
    2) the imode is good type but not S_IFREG.
    3) the imode is S_IFREG.

    The BUG_ON may be triggered by bypassing the check in cases 1 and 2.
    Therefore, when the boot loader inode is bad_inode or its imode is not
    S_IFREG, initialize the inode to avoid triggering the BUG.

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-2026-007516
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?fc21fd94");
  # https://lore.kernel.org/linux-cve-announce/2025120935-CVE-2022-50638-fb89@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?4e238f4c");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2022-50638");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:H/Au:S/C:N/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:H/PR:L/UI:N/S:U/C:N/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-2022-50638");

  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:"2026/04/17");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/17");

  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:"^20.1050e|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-4.19.90-2211.2.0', 'sp':'1050e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.2.0', 'sp':'1050e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.2.0', 'sp':'1050e', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  },
  {
    'release': '20',
    'sp': '1060e',
    'pkgs': [
      {'reference':'kernel-4.19.90-2211.2.0', 'sp':'1060e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.2.0', 'sp':'1060e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.2.0', 'sp':'1060e', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  },
  {
    'release': '20',
    'sp': '1070e',
    'pkgs': [
      {'reference':'kernel-4.19.90-2211.2.0', 'sp':'1070e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.2.0', 'sp':'1070e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.2.0', 'sp':'1070e', 'cpu':'sw_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.2.0', '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');
}