Unity Linux 20.1070a Security Update: kernel (UTSA-2026-005686)

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

include('compat.inc');

if (description)
{
  script_id(300889);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/03/05");

  script_cve_id("CVE-2023-53485");

  script_name(english:"Unity Linux 20.1070a Security Update: kernel (UTSA-2026-005686)");

  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-2026-005686 advisory.

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

    fs: jfs: Fix UBSAN: array-index-out-of-bounds in dbAllocDmapLev

    Syzkaller reported the following issue:

    UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:1965:6
    index -84 is out of range for type 's8[341]' (aka 'signed char[341]')
    CPU: 1 PID: 4995 Comm: syz-executor146 Not tainted 6.4.0-rc6-syzkaller-00037-gb6dad5178cea #0
    Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
    Call Trace:
     <TASK>
     __dump_stack lib/dump_stack.c:88 [inline]
     dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
     ubsan_epilogue lib/ubsan.c:217 [inline]
     __ubsan_handle_out_of_bounds+0x11c/0x150 lib/ubsan.c:348
     dbAllocDmapLev+0x3e5/0x430 fs/jfs/jfs_dmap.c:1965
     dbAllocCtl+0x113/0x920 fs/jfs/jfs_dmap.c:1809
     dbAllocAG+0x28f/0x10b0 fs/jfs/jfs_dmap.c:1350
     dbAlloc+0x658/0xca0 fs/jfs/jfs_dmap.c:874
     dtSplitUp fs/jfs/jfs_dtree.c:974 [inline]
     dtInsert+0xda7/0x6b00 fs/jfs/jfs_dtree.c:863
     jfs_create+0x7b6/0xbb0 fs/jfs/namei.c:137
     lookup_open fs/namei.c:3492 [inline]
     open_last_lookups fs/namei.c:3560 [inline]
     path_openat+0x13df/0x3170 fs/namei.c:3788
     do_filp_open+0x234/0x490 fs/namei.c:3818
     do_sys_openat2+0x13f/0x500 fs/open.c:1356
     do_sys_open fs/open.c:1372 [inline]
     __do_sys_openat fs/open.c:1388 [inline]
     __se_sys_openat fs/open.c:1383 [inline]
     __x64_sys_openat+0x247/0x290 fs/open.c:1383
     do_syscall_x64 arch/x86/entry/common.c:50 [inline]
     do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
     entry_SYSCALL_64_after_hwframe+0x63/0xcd
    RIP: 0033:0x7f1f4e33f7e9
    Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 14 00 00 90 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 c0 ff ff ff f7 d8 64 89 01 48
    RSP: 002b:00007ffc21129578 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
    RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1f4e33f7e9
    RDX: 000000000000275a RSI: 0000000020000040 RDI: 00000000ffffff9c
    RBP: 00007f1f4e2ff080 R08: 0000000000000000 R09: 0000000000000000
    R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1f4e2ff110
    R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
     </TASK>

    The bug occurs when the dbAllocDmapLev()function attempts to access
    dp->tree.stree[leafidx + LEAFIND] while the leafidx value is negative.

    To rectify this, the patch introduces a safeguard within the
    dbAllocDmapLev() function. A check has been added to verify if leafidx is
    negative. If it is, the function immediately returns an I/O error, preventing
    any further execution that could potentially cause harm.

    Tested via syzbot.

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-2026-005686
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?9811d66d");
  # https://lore.kernel.org/linux-cve-announce/2025100114-CVE-2023-53485-672c@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?77016423");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2023-53485");
  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-2023-53485");

  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:"2026/03/03");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/03/05");

  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:"^20.1070a([^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 && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1070a',
    'pkgs': [
      {'reference':'kernel-4.19.0-91.82.190.007', 'sp':'1070a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.0-91.82.190.007', 'sp':'1070a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.0-91.82.190.007', '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');
}