Unity Linux 20.1050e Security Update: kernel (UTSA-2026-005129)

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

include('compat.inc');

if (description)
{
  script_id(296819);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/01/27");

  script_cve_id("CVE-2024-49884");

  script_name(english:"Unity Linux 20.1050e Security Update: kernel (UTSA-2026-005129)");

  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-2026-005129 advisory.

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

    ext4: fix slab-use-after-free in ext4_split_extent_at()

    We hit the following use-after-free:

    ==================================================================
    BUG: KASAN: slab-use-after-free in ext4_split_extent_at+0xba8/0xcc0
    Read of size 2 at addr ffff88810548ed08 by task kworker/u20:0/40
    CPU: 0 PID: 40 Comm: kworker/u20:0 Not tainted 6.9.0-dirty #724
    Call Trace:
     <TASK>
     kasan_report+0x93/0xc0
     ext4_split_extent_at+0xba8/0xcc0
     ext4_split_extent.isra.0+0x18f/0x500
     ext4_split_convert_extents+0x275/0x750
     ext4_ext_handle_unwritten_extents+0x73e/0x1580
     ext4_ext_map_blocks+0xe20/0x2dc0
     ext4_map_blocks+0x724/0x1700
     ext4_do_writepages+0x12d6/0x2a70
    [...]

    Allocated by task 40:
     __kmalloc_noprof+0x1ac/0x480
     ext4_find_extent+0xf3b/0x1e70
     ext4_ext_map_blocks+0x188/0x2dc0
     ext4_map_blocks+0x724/0x1700
     ext4_do_writepages+0x12d6/0x2a70
    [...]

    Freed by task 40:
     kfree+0xf1/0x2b0
     ext4_find_extent+0xa71/0x1e70
     ext4_ext_insert_extent+0xa22/0x3260
     ext4_split_extent_at+0x3ef/0xcc0
     ext4_split_extent.isra.0+0x18f/0x500
     ext4_split_convert_extents+0x275/0x750
     ext4_ext_handle_unwritten_extents+0x73e/0x1580
     ext4_ext_map_blocks+0xe20/0x2dc0
     ext4_map_blocks+0x724/0x1700
     ext4_do_writepages+0x12d6/0x2a70
    [...]
    ==================================================================

    The flow of issue triggering is as follows:

    ext4_split_extent_at
      path = *ppath
      ext4_ext_insert_extent(ppath)
        ext4_ext_create_new_leaf(ppath)
          ext4_find_extent(orig_path)
            path = *orig_path
            read_extent_tree_block
              // return -ENOMEM or -EIO
            ext4_free_ext_path(path)
              kfree(path)
            *orig_path = NULL
      a. If err is -ENOMEM:
      ext4_ext_dirty(path + path->p_depth)
      // path use-after-free !!!
      b. If err is -EIO and we have EXT_DEBUG defined:
      ext4_ext_show_leaf(path)
        eh = path[depth].p_hdr
        // path also use-after-free !!!

    So when trying to zeroout or fix the extent length, call ext4_find_extent()
    to update the path.

    In addition we use *ppath directly as an ext4_ext_show_leaf() input to
    avoid possible use-after-free when EXT_DEBUG is defined, and to avoid
    unnecessary path updates.

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-2026-005129
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?e9f37620");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2024-49884");
  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-2024-49884");

  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:"2023/12/12");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/01/28");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/01/27");

  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');
}