Unity Linux 20.1050e Security Update: kernel (UTSA-2026-006642)

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

include('compat.inc');

if (description)
{
  script_id(305450);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/08");

  script_cve_id("CVE-2022-49443");

  script_name(english:"Unity Linux 20.1050e Security Update: kernel (UTSA-2026-006642)");

  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-2026-006642 advisory.

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

    list: fix a data-race around ep->rdllist

    ep_poll() first calls ep_events_available() with no lock held and checks
    if ep->rdllist is empty by list_empty_careful(), which reads
    rdllist->prev.  Thus all accesses to it need some protection to avoid
    store/load-tearing.

    Note INIT_LIST_HEAD_RCU() already has the annotation for both prev
    and next.

    Commit bf3b9f6372c4 (epoll: Add busy poll support to epoll with socket
    fds.) added the first lockless ep_events_available(), and commit
    c5a282e9635e (fs/epoll: reduce the scope of wq lock in epoll_wait())
    made some ep_events_available() calls lockless and added single call under
    a lock, finally commit e59d3c64cba6 (epoll: eliminate unnecessary lock
    for zero timeout) made the last ep_events_available() lockless.

    BUG: KCSAN: data-race in do_epoll_wait / do_epoll_wait

    write to 0xffff88810480c7d8 of 8 bytes by task 1802 on cpu 0:
     INIT_LIST_HEAD include/linux/list.h:38 [inline]
     list_splice_init include/linux/list.h:492 [inline]
     ep_start_scan fs/eventpoll.c:622 [inline]
     ep_send_events fs/eventpoll.c:1656 [inline]
     ep_poll fs/eventpoll.c:1806 [inline]
     do_epoll_wait+0x4eb/0xf40 fs/eventpoll.c:2234
     do_epoll_pwait fs/eventpoll.c:2268 [inline]
     __do_sys_epoll_pwait fs/eventpoll.c:2281 [inline]
     __se_sys_epoll_pwait+0x12b/0x240 fs/eventpoll.c:2275
     __x64_sys_epoll_pwait+0x74/0x80 fs/eventpoll.c:2275
     do_syscall_x64 arch/x86/entry/common.c:50 [inline]
     do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
     entry_SYSCALL_64_after_hwframe+0x44/0xae

    read to 0xffff88810480c7d8 of 8 bytes by task 1799 on cpu 1:
     list_empty_careful include/linux/list.h:329 [inline]
     ep_events_available fs/eventpoll.c:381 [inline]
     ep_poll fs/eventpoll.c:1797 [inline]
     do_epoll_wait+0x279/0xf40 fs/eventpoll.c:2234
     do_epoll_pwait fs/eventpoll.c:2268 [inline]
     __do_sys_epoll_pwait fs/eventpoll.c:2281 [inline]
     __se_sys_epoll_pwait+0x12b/0x240 fs/eventpoll.c:2275
     __x64_sys_epoll_pwait+0x74/0x80 fs/eventpoll.c:2275
     do_syscall_x64 arch/x86/entry/common.c:50 [inline]
     do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
     entry_SYSCALL_64_after_hwframe+0x44/0xae

    value changed: 0xffff88810480c7d0 -> 0xffff888103c15098

    Reported by Kernel Concurrency Sanitizer on:
    CPU: 1 PID: 1799 Comm: syz-fuzzer Tainted: G        W         5.17.0-rc7-syzkaller-dirty #0
    Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

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-2026-006642
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?d2eaeab7");
  # https://lore.kernel.org/linux-cve-announce/2025022658-CVE-2022-49443-15cc@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?f7bc2120");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2022-49443");
  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: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:H/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-2022-49443");

  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:"2026/04/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/08");

  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-4.19.90-2211.5.0.0178.51', 'sp':'1050e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.5.0.0178.51', 'sp':'1050e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.90-2211.5.0.0178.51', '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_NOTE,
      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');
}