Unity Linux 20.1070a Security Update: kernel (UTSA-2025-990604)

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

include('compat.inc');

if (description)
{
  script_id(274206);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/11/06");

  script_cve_id("CVE-2022-49526");

  script_name(english:"Unity Linux 20.1070a Security Update: kernel (UTSA-2025-990604)");

  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-2025-990604 advisory.

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

    md/bitmap: don't set sb values if can't pass sanity check

    If bitmap area contains invalid data, kernel will crash then mdadm
    triggers Segmentation fault.
    This is cluster-md speical bug. In non-clustered env, mdadm will
    handle broken metadata case. In clustered array, only kernel space
    handles bitmap slot info. But even this bug only happened in clustered
    env, current sanity check is wrong, the code should be changed.

    How to trigger: (faulty injection)

    dd if=/dev/zero bs=1M count=1 oflag=direct of=/dev/sda
    dd if=/dev/zero bs=1M count=1 oflag=direct of=/dev/sdb
    mdadm -C /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda /dev/sdb
    mdadm -Ss
    echo aaa > magic.txt
     == below modifying slot 2 bitmap data ==
    dd if=magic.txt of=/dev/sda seek=16384 bs=1 count=3 <== destroy magic
    dd if=/dev/zero of=/dev/sda seek=16436 bs=1 count=4 <== ZERO chunksize
    mdadm -A /dev/md0 /dev/sda /dev/sdb
     == kernel crashes. mdadm outputs Segmentation fault ==

    Reason of kernel crash:

    In md_bitmap_read_sb (called by md_bitmap_create), bad bitmap magic didn't
    block chunksize assignment, and zero value made DIV_ROUND_UP_SECTOR_T()
    trigger divide error.

    Crash log:

    kernel: md: md0 stopped.
    kernel: md/raid1:md0: not clean -- starting background reconstruction
    kernel: md/raid1:md0: active with 2 out of 2 mirrors
    kernel: dlm: ... ...
    kernel: md-cluster: Joined cluster 44810aba-38bb-e6b8-daca-bc97a0b254aa slot 1
    kernel: md0: invalid bitmap file superblock: bad magic
    kernel: md_bitmap_copy_from_slot can't get bitmap from slot 2
    kernel: md-cluster: Could not gather bitmaps from slot 2
    kernel: divide error: 0000 [#1] SMP NOPTI
    kernel: CPU: 0 PID: 1603 Comm: mdadm Not tainted 5.14.6-1-default
    kernel: Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
    kernel: RIP: 0010:md_bitmap_create+0x1d1/0x850 [md_mod]
    kernel: RSP: 0018:ffffc22ac0843ba0 EFLAGS: 00010246
    kernel: ... ...
    kernel: Call Trace:
    kernel:  ? dlm_lock_sync+0xd0/0xd0 [md_cluster 77fe..7a0]
    kernel:  md_bitmap_copy_from_slot+0x2c/0x290 [md_mod 24ea..d3a]
    kernel:  load_bitmaps+0xec/0x210 [md_cluster 77fe..7a0]
    kernel:  md_bitmap_load+0x81/0x1e0 [md_mod 24ea..d3a]
    kernel:  do_md_run+0x30/0x100 [md_mod 24ea..d3a]
    kernel:  md_ioctl+0x1290/0x15a0 [md_mod 24ea....d3a]
    kernel:  ? mddev_unlock+0xaa/0x130 [md_mod 24ea..d3a]
    kernel:  ? blkdev_ioctl+0xb1/0x2b0
    kernel:  block_ioctl+0x3b/0x40
    kernel:  __x64_sys_ioctl+0x7f/0xb0
    kernel:  do_syscall_64+0x59/0x80
    kernel:  ? exit_to_user_mode_prepare+0x1ab/0x230
    kernel:  ? syscall_exit_to_user_mode+0x18/0x40
    kernel:  ? do_syscall_64+0x69/0x80
    kernel:  entry_SYSCALL_64_after_hwframe+0x44/0xae
    kernel: RIP: 0033:0x7f4a15fa722b
    kernel: ... ...
    kernel: ---[ end trace 8afa7612f559c868 ]---
    kernel: RIP: 0010:md_bitmap_create+0x1d1/0x850 [md_mod]

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-2025-990604
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?7690b0c1");
  # https://lore.kernel.org/linux-cve-announce/2025022612-CVE-2022-49526-5b0b@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?7f745b7a");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2022-49526");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/C:N/I:N/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:N/I:N/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-2022-49526");

  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:"2022/07/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/11/06");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/11/06");

  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) 2025 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:"^20.1070a([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 20.1070a', '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 && 'loongarch64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1070a',
    'pkgs': [
      {'reference':'kernel-4.19.0-91.82.190.003', 'sp':'1070a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.0-91.82.190.003', 'sp':'1070a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.0-91.82.190.003', 'sp':'1070a', 'cpu':'loongarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.0-91.82.190.003', 'sp':'1070a', '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');
}