Unity Linux 20.1070e Security Update: kernel (UTSA-2026-131762)

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

include('compat.inc');

if (description)
{
  script_id(366584);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/16");

  script_cve_id("CVE-2022-48689");

  script_name(english:"Unity Linux 20.1070e Security Update: kernel (UTSA-2026-131762)");

  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-2026-131762 advisory.

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

    tcp: TX zerocopy should not sense pfmemalloc status

    We got a recent syzbot report [1] showing a possible misuse
    of pfmemalloc page status in TCP zerocopy paths.

    Indeed, for pages coming from user space or other layers,
    using page_is_pfmemalloc() is moot, and possibly could give
    false positives.

    There has been attempts to make page_is_pfmemalloc() more robust,
    but not using it in the first place in this context is probably better,
    removing cpu cycles.

    Note to stable teams :

    You need to backport 84ce071e38a6 (net: introduce
    __skb_fill_page_desc_noacc) as a prereq.

    Race is more probable after commit c07aea3ef4d4
    (mm: add a signature in struct page) because page_is_pfmemalloc()
    is now using low order bit from page->lru.next, which can change
    more often than page->index.

    Low order bit should never be set for lru.next (when used as an anchor
    in LRU list), so KCSAN report is mostly a false positive.

    Backporting to older kernel versions seems not necessary.

    [1]
    BUG: KCSAN: data-race in lru_add_fn / tcp_build_frag

    write to 0xffffea0004a1d2c8 of 8 bytes by task 18600 on cpu 0:
    __list_add include/linux/list.h:73 [inline]
    list_add include/linux/list.h:88 [inline]
    lruvec_add_folio include/linux/mm_inline.h:105 [inline]
    lru_add_fn+0x440/0x520 mm/swap.c:228
    folio_batch_move_lru+0x1e1/0x2a0 mm/swap.c:246
    folio_batch_add_and_move mm/swap.c:263 [inline]
    folio_add_lru+0xf1/0x140 mm/swap.c:490
    filemap_add_folio+0xf8/0x150 mm/filemap.c:948
    __filemap_get_folio+0x510/0x6d0 mm/filemap.c:1981
    pagecache_get_page+0x26/0x190 mm/folio-compat.c:104
    grab_cache_page_write_begin+0x2a/0x30 mm/folio-compat.c:116
    ext4_da_write_begin+0x2dd/0x5f0 fs/ext4/inode.c:2988
    generic_perform_write+0x1d4/0x3f0 mm/filemap.c:3738
    ext4_buffered_write_iter+0x235/0x3e0 fs/ext4/file.c:270
    ext4_file_write_iter+0x2e3/0x1210
    call_write_iter include/linux/fs.h:2187 [inline]
    new_sync_write fs/read_write.c:491 [inline]
    vfs_write+0x468/0x760 fs/read_write.c:578
    ksys_write+0xe8/0x1a0 fs/read_write.c:631
    __do_sys_write fs/read_write.c:643 [inline]
    __se_sys_write fs/read_write.c:640 [inline]
    __x64_sys_write+0x3e/0x50 fs/read_write.c:640
    do_syscall_x64 arch/x86/entry/common.c:50 [inline]
    do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
    entry_SYSCALL_64_after_hwframe+0x63/0xcd

    read to 0xffffea0004a1d2c8 of 8 bytes by task 18611 on cpu 1:
    page_is_pfmemalloc include/linux/mm.h:1740 [inline]
    __skb_fill_page_desc include/linux/skbuff.h:2422 [inline]
    skb_fill_page_desc include/linux/skbuff.h:2443 [inline]
    tcp_build_frag+0x613/0xb20 net/ipv4/tcp.c:1018
    do_tcp_sendpages+0x3e8/0xaf0 net/ipv4/tcp.c:1075
    tcp_sendpage_locked net/ipv4/tcp.c:1140 [inline]
    tcp_sendpage+0x89/0xb0 net/ipv4/tcp.c:1150
    inet_sendpage+0x7f/0xc0 net/ipv4/af_inet.c:833
    kernel_sendpage+0x184/0x300 net/socket.c:3561
    sock_sendpage+0x5a/0x70 net/socket.c:1054
    pipe_to_sendpage+0x128/0x160 fs/splice.c:361
    splice_from_pipe_feed fs/splice.c:415 [inline]
    __splice_from_pipe+0x222/0x4d0 fs/splice.c:559
    splice_from_pipe fs/splice.c:594 [inline]
    generic_splice_sendpage+0x89/0xc0 fs/splice.c:743
    do_splice_from fs/splice.c:764 [inline]
    direct_splice_actor+0x80/0xa0 fs/splice.c:931
    splice_direct_to_actor+0x305/0x620 fs/splice.c:886
    do_splice_direct+0xfb/0x180 fs/splice.c:974
    do_sendfile+0x3bf/0x910 fs/read_write.c:1249
    __do_sys_sendfile64 fs/read_write.c:1317 [inline]
    __se_sys_sendfile64 fs/read_write.c:1303 [inline]
    __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1303
    do_syscall_x64 arch/x86/entry/common.c:50 [inline]
    do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
    entry_SYSCALL_64_after_hwframe+0x63/0xcd

    value changed: 0x0000000000000000 -> 0xffffea0004a1d288

    Reported by Kernel Concurrency Sanitizer on:
    CPU: 1 PID: 18611 Comm: syz-executor.4 Not tainted 6.0.0-rc2-syzkaller-00248-ge022620b5d05-dirty #0
    Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022

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-2026-131762
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?c72cc1d6");
  # https://lore.kernel.org/linux-cve-announce/2024050345-CVE-2022-48689-5ee7@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?fdcfad20");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2022-48689");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:H/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:H/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-2022-48689");

  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:"2022/10/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/10/16");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/16");

  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:"^(20.1070e)([^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 && 'sw_64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1070e',
    'pkgs': [
      {'reference':'kernel-5.10.0-79.26.uel20', 'sp':'1070e', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.26.uel20', 'sp':'1070e', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.26.uel20', 'sp':'1070e', 'cpu':'sw_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-79.26.uel20', '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');
}