Ubuntu 20.04 LTS : Linux kernel (IoT) vulnerabilities (USN-6548-5)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-6548-5. 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(187934);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/06/19");

  script_cve_id(
    "CVE-2023-3006",
    "CVE-2023-5178",
    "CVE-2023-5717",
    "CVE-2023-6176",
    "CVE-2023-37453",
    "CVE-2023-39189",
    "CVE-2023-39192",
    "CVE-2023-39193",
    "CVE-2023-39194",
    "CVE-2023-42754"
  );
  script_xref(name:"USN", value:"6548-5");

  script_name(english:"Ubuntu 20.04 LTS : Linux kernel (IoT) vulnerabilities (USN-6548-5)");

  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 20.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in
the USN-6548-5 advisory.

  - A known cache speculation vulnerability, known as Branch History Injection (BHI) or Spectre-BHB, becomes
    actual again for the new hw AmpereOne. Spectre-BHB is similar to Spectre v2, except that malicious code
    uses the shared branch history (stored in the CPU Branch History Buffer, or BHB) to influence mispredicted
    branches within the victim's hardware context. Once that occurs, speculation caused by the mispredicted
    branches can cause cache allocation. This issue leads to obtaining information that should not be
    accessible. (CVE-2023-3006)

  - An issue was discovered in the USB subsystem in the Linux kernel through 6.4.2. There is an out-of-bounds
    and crash in read_descriptors in drivers/usb/core/sysfs.c. (CVE-2023-37453)

  - A flaw was found in the Netfilter subsystem in the Linux kernel. The nfnl_osf_add_callback function did
    not validate the user mode controlled opt_num field. This flaw allows a local privileged (CAP_NET_ADMIN)
    attacker to trigger an out-of-bounds read, leading to a crash or information disclosure. (CVE-2023-39189)

  - A flaw was found in the Netfilter subsystem in the Linux kernel. The xt_u32 module did not validate the
    fields in the xt_u32 structure. This flaw allows a local privileged attacker to trigger an out-of-bounds
    read by setting the size fields with a value beyond the array boundaries, leading to a crash or
    information disclosure. (CVE-2023-39192)

  - A flaw was found in the Netfilter subsystem in the Linux kernel. The sctp_mt_check did not validate the
    flag_count field. This flaw allows a local privileged (CAP_NET_ADMIN) attacker to trigger an out-of-bounds
    read, leading to a crash or information disclosure. (CVE-2023-39193)

  - A flaw was found in the XFRM subsystem in the Linux kernel. The specific flaw exists within the processing
    of state filters, which can result in a read past the end of an allocated buffer. This flaw allows a local
    privileged (CAP_NET_ADMIN) attacker to trigger an out-of-bounds read, potentially leading to an
    information disclosure. (CVE-2023-39194)

  - A NULL pointer dereference flaw was found in the Linux kernel ipv4 stack. The socket buffer (skb) was
    assumed to be associated with a device before calling __ip_options_compile, which is not always the case
    if the skb is re-routed by ipvs. This issue may allow a local user with CAP_NET_ADMIN privileges to crash
    the system. (CVE-2023-42754)

  - A use-after-free vulnerability was found in drivers/nvme/target/tcp.c` in `nvmet_tcp_free_crypto` due to a
    logical bug in the NVMe-oF/TCP subsystem in the Linux kernel. This issue may allow a malicious local
    privileged user to cause a use-after-free and double-free problem, which may permit remote code execution
    or lead to local privilege escalation problem. (CVE-2023-5178)

  - A heap out-of-bounds write vulnerability in the Linux kernel's Linux Kernel Performance Events (perf)
    component can be exploited to achieve local privilege escalation. If perf_read_group() is called while an
    event's sibling_list is smaller than its child's sibling_list, it can increment or write to memory
    locations outside of the allocated buffer. We recommend upgrading past commit
    32671e3799ca2e4590773fd0e63aaa4229e50c06. (CVE-2023-5717)

  - A null pointer dereference flaw was found in the Linux kernel API for the cryptographic algorithm
    scatterwalk functionality. This issue occurs when a user constructs a malicious packet with specific
    socket configuration, which could allow a local user to crash the system or escalate their privileges on
    the system. (CVE-2023-6176)

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-6548-5");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/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-2023-5178");

  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:"2023/05/31");
  script_set_attribute(attribute:"patch_publication_date", value:"2024/01/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2024/01/10");

  script_set_attribute(attribute:"plugin_type", value:"local");
  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-5.4.0-1028-iot");
  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 (! ('20.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 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 = {
  '20.04': {
    '5.4.0': {
      'iot': '5.4.0-1028'
    }
  }
};

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-6548-5');
}

if (get_one_kb_item('Host/ksplice/kernel-cves'))
{
  var cve_list = make_list('CVE-2023-3006', 'CVE-2023-5178', 'CVE-2023-5717', 'CVE-2023-6176', 'CVE-2023-37453', 'CVE-2023-39189', 'CVE-2023-39192', 'CVE-2023-39193', 'CVE-2023-39194', 'CVE-2023-42754');
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, 'KSplice hotfix for USN-6548-5');
  }
  else
  {
    extra = extra + ksplice_reporting_text();
  }
}
if (extra) {
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : extra
  );
  exit(0);
}