Ubuntu 18.04 LTS / 20.04 LTS : Linux kernel vulnerabilities (USN-6681-2)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-6681-2. The text
# itself is copyright (C) Canonical, Inc. See
# <https://ubuntu.com/security/notices>. Ubuntu(R) is a registered
# trademark of Canonical, Inc.
##

include('compat.inc');

if (description)
{
  script_id(191795);
  script_version("1.0");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/03/11");

  script_cve_id(
    "CVE-2021-44879",
    "CVE-2023-4244",
    "CVE-2023-6121",
    "CVE-2023-22995",
    "CVE-2023-51779",
    "CVE-2023-51780",
    "CVE-2023-51782",
    "CVE-2024-0340"
  );
  script_xref(name:"USN", value:"6681-2");

  script_name(english:"Ubuntu 18.04 LTS / 20.04 LTS : Linux kernel vulnerabilities (USN-6681-2)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Ubuntu 18.04 LTS / 20.04 LTS host has a package installed that is affected by multiple vulnerabilities as
referenced in the USN-6681-2 advisory.

  - In gc_data_segment in fs/f2fs/gc.c in the Linux kernel before 5.16.3, special files are not considered,
    leading to a move_data_page NULL pointer dereference. (CVE-2021-44879)

  - In the Linux kernel before 5.17, an error path in dwc3_qcom_acpi_register_core in
    drivers/usb/dwc3/dwc3-qcom.c lacks certain platform_device_put and kfree calls. (CVE-2023-22995)

  - A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to
    achieve local privilege escalation. Due to a race condition between nf_tables netlink control plane
    transaction and nft_set element garbage collection, it is possible to underflow the reference counter
    causing a use-after-free vulnerability. We recommend upgrading past commit
    3e91b0ebd994635df2346353322ac51ce84ce6d8. (CVE-2023-4244)

  - bt_sock_recvmsg in net/bluetooth/af_bluetooth.c in the Linux kernel through 6.6.8 has a use-after-free
    because of a bt_sock_ioctl race condition. (CVE-2023-51779)

  - An issue was discovered in the Linux kernel before 6.6.8. do_vcc_ioctl in net/atm/ioctl.c has a use-after-
    free because of a vcc_recvmsg race condition. (CVE-2023-51780)

  - An issue was discovered in the Linux kernel before 6.6.8. rose_ioctl in net/rose/af_rose.c has a use-
    after-free because of a rose_accept race condition. (CVE-2023-51782)

  - An out-of-bounds read vulnerability was found in the NVMe-oF/TCP subsystem in the Linux kernel. This issue
    may allow a remote attacker to send a crafted TCP packet, triggering a heap-based buffer overflow that
    results in kmalloc data being printed and potentially leaked to the kernel ring buffer (dmesg).
    (CVE-2023-6121)

  - A vulnerability was found in vhost_new_msg in drivers/vhost/vhost.c in the Linux kernel, which does not
    properly initialize memory in messages passed between virtual guests and the host operating system in the
    vhost/vhost.c:vhost_new_msg() function. This issue can allow local privileged users to read some kernel
    memory contents when reading from the /dev/vhost-net device file. (CVE-2024-0340)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/notices/USN-6681-2");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:N/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:POC/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:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-44879");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2023-22995");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2022/02/14");
  script_set_attribute(attribute:"patch_publication_date", value:"2024/03/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2024/03/11");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4.0-1039-xilinx-zynqmp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4.0-1080-bluefield");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4.0-1104-raspi");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Ubuntu Local Security Checks");

  script_copyright(english:"Ubuntu Security Notice (C) 2024 Canonical, Inc. / NASL script (C) 2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl", "linux_alt_patch_detect.nasl");
  script_require_keys("Host/cpu", "Host/Ubuntu", "Host/Ubuntu/release", "Host/Debian/dpkg-l");

  exit(0);
}

include('debian_package.inc');
include('ksplice.inc');

if ( ! get_kb_item('Host/local_checks_enabled') ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_release = get_kb_item('Host/Ubuntu/release');
if ( isnull(os_release) ) audit(AUDIT_OS_NOT, 'Ubuntu');
os_release = chomp(os_release);
if (! ('18.04' >< os_release || '20.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 18.04 / 20.04', 'Ubuntu ' + os_release);
if ( ! get_kb_item('Host/Debian/dpkg-l') ) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 's390' >!< cpu && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Ubuntu', cpu);

var kernel_mappings = {
  '18.04': {
    '5.4.0': {
      'raspi': '5.4.0-1104'
    }
  },
  '20.04': {
    '5.4.0': {
      'xilinx-zynqmp': '5.4.0-1039',
      'bluefield': '5.4.0-1080'
    }
  }
};

var host_kernel_release = get_kb_item('Host/uptrack-uname-r');
if (empty_or_null(host_kernel_release)) host_kernel_release = get_kb_item_or_exit('Host/uname-r');
var host_kernel_base_version = get_kb_item_or_exit('Host/Debian/kernel-base-version');
var host_kernel_type = get_kb_item_or_exit('Host/Debian/kernel-type');
if(empty_or_null(kernel_mappings[os_release][host_kernel_base_version][host_kernel_type])) audit(AUDIT_INST_VER_NOT_VULN, 'kernel ' + host_kernel_release);

var extra = '';
var kernel_fixed_version = kernel_mappings[os_release][host_kernel_base_version][host_kernel_type] + "-" + host_kernel_type;
if (deb_ver_cmp(ver1:host_kernel_release, ver2:kernel_fixed_version) < 0)
{
  extra = extra + 'Running Kernel level of ' + host_kernel_release + ' does not meet the minimum fixed level of ' + kernel_fixed_version + ' for this advisory.\n\n';
}
  else
{
  audit(AUDIT_PATCH_INSTALLED, 'Kernel package for USN-6681-2');
}

if (get_one_kb_item('Host/ksplice/kernel-cves'))
{
  var cve_list = make_list('CVE-2021-44879', 'CVE-2023-4244', 'CVE-2023-6121', 'CVE-2023-22995', 'CVE-2023-51779', 'CVE-2023-51780', 'CVE-2023-51782', 'CVE-2024-0340');
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, 'KSplice hotfix for USN-6681-2');
  }
  else
  {
    extra = extra + ksplice_reporting_text();
  }
}
if (extra) {
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : extra
  );
  exit(0);
}