Unity Linux 20.1070a Security Update: kernel (UTSA-2025-988828)

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

include('compat.inc');

if (description)
{
  script_id(274050);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/11/05");

  script_cve_id("CVE-2021-47572");

  script_name(english:"Unity Linux 20.1070a Security Update: kernel (UTSA-2025-988828)");

  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-2025-988828 advisory.

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

    net: nexthop: fix null pointer dereference when IPv6 is not enabled

    When we try to add an IPv6 nexthop and IPv6 is not enabled
    (!CONFIG_IPV6) we'll hit a NULL pointer dereference[1] in the error path
    of nh_create_ipv6() due to calling ipv6_stub->fib6_nh_release. The bug
    has been present since the beginning of IPv6 nexthop gateway support.
    Commit 1aefd3de7bc6 (ipv6: Add fib6_nh_init and release to stubs) tells
    us that only fib6_nh_init has a dummy stub because fib6_nh_release should
    not be called if fib6_nh_init returns an error, but the commit below added
    a call to ipv6_stub->fib6_nh_release in its error path. To fix it return
    the dummy stub's -EAFNOSUPPORT error directly without calling
    ipv6_stub->fib6_nh_release in nh_create_ipv6()'s error path.

    [1]
     Output is a bit truncated, but it clearly shows the error.
     BUG: kernel NULL pointer dereference, address: 000000000000000000
     #PF: supervisor instruction fetch in kernel modede
     #PF: error_code(0x0010) - not-present pagege
     PGD 0 P4D 0
     Oops: 0010 [#1] PREEMPT SMP NOPTI
     CPU: 4 PID: 638 Comm: ip Kdump: loaded Not tainted 5.16.0-rc1+ #446
     Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-4.fc34 04/01/2014
     RIP: 0010:0x0
     Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
     RSP: 0018:ffff888109f5b8f0 EFLAGS: 00010286^Ac
     RAX: 0000000000000000 RBX: ffff888109f5ba28 RCX: 0000000000000000
     RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8881008a2860
     RBP: ffff888109f5b9d8 R08: 0000000000000000 R09: 0000000000000000
     R10: ffff888109f5b978 R11: ffff888109f5b948 R12: 00000000ffffff9f
     R13: ffff8881008a2a80 R14: ffff8881008a2860 R15: ffff8881008a2840
     FS:  00007f98de70f100(0000) GS:ffff88822bf00000(0000) knlGS:0000000000000000
     CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
     CR2: ffffffffffffffd6 CR3: 0000000100efc000 CR4: 00000000000006e0
     Call Trace:
      <TASK>
      nh_create_ipv6+0xed/0x10c
      rtm_new_nexthop+0x6d7/0x13f3
      ? check_preemption_disabled+0x3d/0xf2
      ? lock_is_held_type+0xbe/0xfd
      rtnetlink_rcv_msg+0x23f/0x26a
      ? check_preemption_disabled+0x3d/0xf2
      ? rtnl_calcit.isra.0+0x147/0x147
      netlink_rcv_skb+0x61/0xb2
      netlink_unicast+0x100/0x187
      netlink_sendmsg+0x37f/0x3a0
      ? netlink_unicast+0x187/0x187
      sock_sendmsg_nosec+0x67/0x9b
      ____sys_sendmsg+0x19d/0x1f9
      ? copy_msghdr_from_user+0x4c/0x5e
      ? rcu_read_lock_any_held+0x2a/0x78
      ___sys_sendmsg+0x6c/0x8c
      ? asm_sysvec_apic_timer_interrupt+0x12/0x20
      ? lockdep_hardirqs_on+0xd9/0x102
      ? sockfd_lookup_light+0x69/0x99
      __sys_sendmsg+0x50/0x6e
      do_syscall_64+0xcb/0xf2
      entry_SYSCALL_64_after_hwframe+0x44/0xae
     RIP: 0033:0x7f98dea28914
     Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b5 0f 1f 80 00 00 00 00 48 8d 05 e9 5d 0c 00 8b 00 85 c0
    75 13 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 41 54 41 89 d4 55 48 89 f5 53
     RSP: 002b:00007fff859f5e68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e2e
     RAX: ffffffffffffffda RBX: 00000000619cb810 RCX: 00007f98dea28914
     RDX: 0000000000000000 RSI: 00007fff859f5ed0 RDI: 0000000000000003
     RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000008
     R10: fffffffffffffce6 R11: 0000000000000246 R12: 0000000000000001
     R13: 000055c0097ae520 R14: 000055c0097957fd R15: 00007fff859f63a0
     </TASK>
     Modules linked in: bridge stp llc bonding virtio_net

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-2025-988828
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?6c55ae6a");
  # https://lore.kernel.org/linux-cve-announce/2024052454-CVE-2021-47572-50bc@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?001afa0a");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2021-47572");
  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-2021-47572");

  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:"2025/11/05");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/11/05");

  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) 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:"^20.1070a([^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 && 'loongarch64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1070a',
    'pkgs': [
      {'reference':'kernel-5.10.0-79.4.2', 'sp':'1070a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.4.2', 'sp':'1070a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.4.2', 'sp':'1070a', 'cpu':'loongarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.4.2', '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');
}