Unity Linux 20.1070a Security Update: kernel (UTSA-2026-005745)

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

include('compat.inc');

if (description)
{
  script_id(300965);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/03/05");

  script_cve_id("CVE-2023-53296");

  script_name(english:"Unity Linux 20.1070a Security Update: kernel (UTSA-2026-005745)");

  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-2026-005745 advisory.

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

    sctp: check send stream number after wait_for_sndbuf

    This patch fixes a corner case where the asoc out stream count may change
    after wait_for_sndbuf.

    When the main thread in the client starts a connection, if its out stream
    count is set to N while the in stream count in the server is set to N - 2,
    another thread in the client keeps sending the msgs with stream number
    N - 1, and waits for sndbuf before processing INIT_ACK.

    However, after processing INIT_ACK, the out stream count in the client is
    shrunk to N - 2, the same to the in stream count in the server. The crash
    occurs when the thread waiting for sndbuf is awake and sends the msg in a
    non-existing stream(N - 1), the call trace is as below:

      KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]
      Call Trace:
       <TASK>
       sctp_cmd_send_msg net/sctp/sm_sideeffect.c:1114 [inline]
       sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1777 [inline]
       sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline]
       sctp_do_sm+0x197d/0x5310 net/sctp/sm_sideeffect.c:1170
       sctp_primitive_SEND+0x9f/0xc0 net/sctp/primitive.c:163
       sctp_sendmsg_to_asoc+0x10eb/0x1a30 net/sctp/socket.c:1868
       sctp_sendmsg+0x8d4/0x1d90 net/sctp/socket.c:2026
       inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:825
       sock_sendmsg_nosec net/socket.c:722 [inline]
       sock_sendmsg+0xde/0x190 net/socket.c:745

    The fix is to add an unlikely check for the send stream number after the
    thread wakes up from the wait_for_sndbuf.

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-2026-005745
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?8ca84dd8");
  # https://lore.kernel.org/linux-cve-announce/2025091627-CVE-2023-53296-9947@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?7f983949");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2023-53296");
  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-2023-53296");

  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-5.10.0-79.7', 'sp':'1070a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.7', 'sp':'1070a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.7', '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');
}