Unity Linux 20.1070a Security Update: kernel (UTSA-2026-013482)

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

include('compat.inc');

if (description)
{
  script_id(309400);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/22");

  script_cve_id("CVE-2022-49142");

  script_name(english:"Unity Linux 20.1070a Security Update: kernel (UTSA-2026-013482)");

  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-2026-013482 advisory.

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

    net: preserve skb_end_offset() in skb_unclone_keeptruesize()

    syzbot found another way to trigger the infamous WARN_ON_ONCE(delta < len)
    in skb_try_coalesce() [1]

    I was able to root cause the issue to kfence.

    When kfence is in action, the following assertion is no longer true:

    int size = xxxx;
    void *ptr1 = kmalloc(size, gfp);
    void *ptr2 = kmalloc(size, gfp);

    if (ptr1 && ptr2)
            ASSERT(ksize(ptr1) == ksize(ptr2));

    We attempted to fix these issues in the blamed commits, but forgot
    that TCP was possibly shifting data after skb_unclone_keeptruesize()
    has been used, notably from tcp_retrans_try_collapse().

    So we not only need to keep same skb->truesize value,
    we also need to make sure TCP wont fill new tailroom
    that pskb_expand_head() was able to get from a
    addr = kmalloc(...) followed by ksize(addr)

    Split skb_unclone_keeptruesize() into two parts:

    1) Inline skb_unclone_keeptruesize() for the common case,
       when skb is not cloned.

    2) Out of line __skb_unclone_keeptruesize() for the 'slow path'.

    WARNING: CPU: 1 PID: 6490 at net/core/skbuff.c:5295 skb_try_coalesce+0x1235/0x1560 net/core/skbuff.c:5295
    Modules linked in:
    CPU: 1 PID: 6490 Comm: syz-executor161 Not tainted 5.17.0-rc4-syzkaller-00229-g4f12b742eb2b #0
    Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
    RIP: 0010:skb_try_coalesce+0x1235/0x1560 net/core/skbuff.c:5295
    Code: bf 01 00 00 00 0f b7 c0 89 c6 89 44 24 20 e8 62 24 4e fa 8b 44 24 20 83 e8 01 0f 85 e5 f0 ff ff e9
    87 f4 ff ff e8 cb 20 4e fa <0f> 0b e9 06 f9 ff ff e8 af b2 95 fa e9 69 f0 ff ff e8 95 b2 95 fa
    RSP: 0018:ffffc900063af268 EFLAGS: 00010293
    RAX: 0000000000000000 RBX: 00000000ffffffd5 RCX: 0000000000000000
    RDX: ffff88806fc05700 RSI: ffffffff872abd55 RDI: 0000000000000003
    RBP: ffff88806e675500 R08: 00000000ffffffd5 R09: 0000000000000000
    R10: ffffffff872ab659 R11: 0000000000000000 R12: ffff88806dd554e8
    R13: ffff88806dd9bac0 R14: ffff88806dd9a2c0 R15: 0000000000000155
    FS:  00007f18014f9700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 0000000020002000 CR3: 000000006be7a000 CR4: 00000000003506f0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
    Call Trace:
     <TASK>
     tcp_try_coalesce net/ipv4/tcp_input.c:4651 [inline]
     tcp_try_coalesce+0x393/0x920 net/ipv4/tcp_input.c:4630
     tcp_queue_rcv+0x8a/0x6e0 net/ipv4/tcp_input.c:4914
     tcp_data_queue+0x11fd/0x4bb0 net/ipv4/tcp_input.c:5025
     tcp_rcv_established+0x81e/0x1ff0 net/ipv4/tcp_input.c:5947
     tcp_v4_do_rcv+0x65e/0x980 net/ipv4/tcp_ipv4.c:1719
     sk_backlog_rcv include/net/sock.h:1037 [inline]
     __release_sock+0x134/0x3b0 net/core/sock.c:2779
     release_sock+0x54/0x1b0 net/core/sock.c:3311
     sk_wait_data+0x177/0x450 net/core/sock.c:2821
     tcp_recvmsg_locked+0xe28/0x1fd0 net/ipv4/tcp.c:2457
     tcp_recvmsg+0x137/0x610 net/ipv4/tcp.c:2572
     inet_recvmsg+0x11b/0x5e0 net/ipv4/af_inet.c:850
     sock_recvmsg_nosec net/socket.c:948 [inline]
     sock_recvmsg net/socket.c:966 [inline]
     sock_recvmsg net/socket.c:962 [inline]
     ____sys_recvmsg+0x2c4/0x600 net/socket.c:2632
     ___sys_recvmsg+0x127/0x200 net/socket.c:2674
     __sys_recvmsg+0xe2/0x1a0 net/socket.c:2704
     do_syscall_x64 arch/x86/entry/common.c:50 [inline]
     do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
     entry_SYSCALL_64_after_hwframe+0x44/0xae

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-2026-013482
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?146d6231");
  # https://lore.kernel.org/linux-cve-announce/2025022607-CVE-2022-49142-b3b9@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?75b47c63");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2022-49142");
  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-2022-49142");

  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:"2022/11/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/04/22");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/22");

  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 && 'loongarch64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1070a',
    'pkgs': [
      {'reference':'kernel-5.10.0-48', 'sp':'1070a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-48', 'sp':'1070a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-48', 'sp':'1070a', 'cpu':'loongarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-5.10.0-48', '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');
}