Unity Linux 20.1050e Security Update: kernel (UTSA-2026-005131)

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

include('compat.inc');

if (description)
{
  script_id(296872);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/01/27");

  script_cve_id("CVE-2024-50035");

  script_name(english:"Unity Linux 20.1050e Security Update: kernel (UTSA-2026-005131)");

  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-2026-005131 advisory.

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

    ppp: fix ppp_async_encode() illegal access

    syzbot reported an issue in ppp_async_encode() [1]

    In this case, pppoe_sendmsg() is called with a zero size.
    Then ppp_async_encode() is called with an empty skb.

    BUG: KMSAN: uninit-value in ppp_async_encode drivers/net/ppp/ppp_async.c:545 [inline]
     BUG: KMSAN: uninit-value in ppp_async_push+0xb4f/0x2660 drivers/net/ppp/ppp_async.c:675
      ppp_async_encode drivers/net/ppp/ppp_async.c:545 [inline]
      ppp_async_push+0xb4f/0x2660 drivers/net/ppp/ppp_async.c:675
      ppp_async_send+0x130/0x1b0 drivers/net/ppp/ppp_async.c:634
      ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2280 [inline]
      ppp_input+0x1f1/0xe60 drivers/net/ppp/ppp_generic.c:2304
      pppoe_rcv_core+0x1d3/0x720 drivers/net/ppp/pppoe.c:379
      sk_backlog_rcv+0x13b/0x420 include/net/sock.h:1113
      __release_sock+0x1da/0x330 net/core/sock.c:3072
      release_sock+0x6b/0x250 net/core/sock.c:3626
      pppoe_sendmsg+0x2b8/0xb90 drivers/net/ppp/pppoe.c:903
      sock_sendmsg_nosec net/socket.c:729 [inline]
      __sock_sendmsg+0x30f/0x380 net/socket.c:744
      ____sys_sendmsg+0x903/0xb60 net/socket.c:2602
      ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2656
      __sys_sendmmsg+0x3c1/0x960 net/socket.c:2742
      __do_sys_sendmmsg net/socket.c:2771 [inline]
      __se_sys_sendmmsg net/socket.c:2768 [inline]
      __x64_sys_sendmmsg+0xbc/0x120 net/socket.c:2768
      x64_sys_call+0xb6e/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:308
      do_syscall_x64 arch/x86/entry/common.c:52 [inline]
      do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
     entry_SYSCALL_64_after_hwframe+0x77/0x7f

    Uninit was created at:
      slab_post_alloc_hook mm/slub.c:4092 [inline]
      slab_alloc_node mm/slub.c:4135 [inline]
      kmem_cache_alloc_node_noprof+0x6bf/0xb80 mm/slub.c:4187
      kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:587
      __alloc_skb+0x363/0x7b0 net/core/skbuff.c:678
      alloc_skb include/linux/skbuff.h:1322 [inline]
      sock_wmalloc+0xfe/0x1a0 net/core/sock.c:2732
      pppoe_sendmsg+0x3a7/0xb90 drivers/net/ppp/pppoe.c:867
      sock_sendmsg_nosec net/socket.c:729 [inline]
      __sock_sendmsg+0x30f/0x380 net/socket.c:744
      ____sys_sendmsg+0x903/0xb60 net/socket.c:2602
      ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2656
      __sys_sendmmsg+0x3c1/0x960 net/socket.c:2742
      __do_sys_sendmmsg net/socket.c:2771 [inline]
      __se_sys_sendmmsg net/socket.c:2768 [inline]
      __x64_sys_sendmmsg+0xbc/0x120 net/socket.c:2768
      x64_sys_call+0xb6e/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:308
      do_syscall_x64 arch/x86/entry/common.c:52 [inline]
      do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
     entry_SYSCALL_64_after_hwframe+0x77/0x7f

    CPU: 1 UID: 0 PID: 5411 Comm: syz.1.14 Not tainted 6.12.0-rc1-syzkaller-00165-g360c1f1f24c6 #0
    Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024

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-2026-005131
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?3197afc8");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2024-50035");
  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: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:H/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-2024-50035");

  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:"2024/04/09");
  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');
}