Unity Linux 20.1070e Security Update: kernel (UTSA-2025-987338)

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

include('compat.inc');

if (description)
{
  script_id(267964);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/10/15");

  script_cve_id("CVE-2022-49840");

  script_name(english:"Unity Linux 20.1070e Security Update: kernel (UTSA-2025-987338)");

  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-2025-987338 advisory.

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

    bpf, test_run: Fix alignment problem in bpf_prog_test_run_skb()

    We got a syzkaller problem because of aarch64 alignment fault
    if KFENCE enabled. When the size from user bpf program is an odd
    number, like 399, 407, etc, it will cause the struct skb_shared_info's
    unaligned access. As seen below:

      BUG: KFENCE: use-after-free read in __skb_clone+0x23c/0x2a0 net/core/skbuff.c:1032

      Use-after-free read at 0xffff6254fffac077 (in kfence-#213):
       __lse_atomic_add arch/arm64/include/asm/atomic_lse.h:26 [inline]
       arch_atomic_add arch/arm64/include/asm/atomic.h:28 [inline]
       arch_atomic_inc include/linux/atomic-arch-fallback.h:270 [inline]
       atomic_inc include/asm-generic/atomic-instrumented.h:241 [inline]
       __skb_clone+0x23c/0x2a0 net/core/skbuff.c:1032
       skb_clone+0xf4/0x214 net/core/skbuff.c:1481
       ____bpf_clone_redirect net/core/filter.c:2433 [inline]
       bpf_clone_redirect+0x78/0x1c0 net/core/filter.c:2420
       bpf_prog_d3839dd9068ceb51+0x80/0x330
       bpf_dispatcher_nop_func include/linux/bpf.h:728 [inline]
       bpf_test_run+0x3c0/0x6c0 net/bpf/test_run.c:53
       bpf_prog_test_run_skb+0x638/0xa7c net/bpf/test_run.c:594
       bpf_prog_test_run kernel/bpf/syscall.c:3148 [inline]
       __do_sys_bpf kernel/bpf/syscall.c:4441 [inline]
       __se_sys_bpf+0xad0/0x1634 kernel/bpf/syscall.c:4381

      kfence-#213: 0xffff6254fffac000-0xffff6254fffac196, size=407, cache=kmalloc-512

      allocated by task 15074 on cpu 0 at 1342.585390s:
       kmalloc include/linux/slab.h:568 [inline]
       kzalloc include/linux/slab.h:675 [inline]
       bpf_test_init.isra.0+0xac/0x290 net/bpf/test_run.c:191
       bpf_prog_test_run_skb+0x11c/0xa7c net/bpf/test_run.c:512
       bpf_prog_test_run kernel/bpf/syscall.c:3148 [inline]
       __do_sys_bpf kernel/bpf/syscall.c:4441 [inline]
       __se_sys_bpf+0xad0/0x1634 kernel/bpf/syscall.c:4381
       __arm64_sys_bpf+0x50/0x60 kernel/bpf/syscall.c:4381

    To fix the problem, we adjust @size so that (@size + @hearoom) is a
    multiple of SMP_CACHE_BYTES. So we make sure the struct skb_shared_info
    is aligned to a cache line.

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-2025-987338
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?8fa507c1");
  # https://lore.kernel.org/linux-cve-announce/2025050140-CVE-2022-49840-5186@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?d4dd54f9");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2022-49840");
  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-2022-49840");

  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:"2022/12/12");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/09/23");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/10/07");

  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:"^20.1070e([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 20.1070e', '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': '1070e',
    'pkgs': [
      {'reference':'kernel-5.10.0-74.16', 'sp':'1070e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-74.16', 'sp':'1070e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-74.16', 'sp':'1070e', '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');
}