Ubuntu 16.04 ESM / 18.04 ESM : Linux kernel (Azure) vulnerabilities (USN-6342-2)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-6342-2. 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(181186);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/01/09");

  script_cve_id(
    "CVE-2023-2269",
    "CVE-2023-2985",
    "CVE-2023-3611",
    "CVE-2023-3776",
    "CVE-2023-20593",
    "CVE-2023-31084"
  );
  script_xref(name:"USN", value:"6342-2");

  script_name(english:"Ubuntu 16.04 ESM / 18.04 ESM : Linux kernel (Azure) vulnerabilities (USN-6342-2)");

  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 16.04 ESM / 18.04 ESM host has a package installed that is affected by multiple vulnerabilities as
referenced in the USN-6342-2 advisory.

  - An issue in Zen 2 CPUs, under specific microarchitectural circumstances, may allow an attacker to
    potentially access sensitive information. (CVE-2023-20593)

  - A denial of service problem was found, due to a possible recursive locking scenario, resulting in a
    deadlock in table_clear in drivers/md/dm-ioctl.c in the Linux Kernel Device Mapper-Multipathing sub-
    component. (CVE-2023-2269)

  - A use after free flaw was found in hfsplus_put_super in fs/hfsplus/super.c in the Linux Kernel. This flaw
    could allow a local user to cause a denial of service problem. (CVE-2023-2985)

  - An issue was discovered in drivers/media/dvb-core/dvb_frontend.c in the Linux kernel 6.2. There is a
    blocking operation when a task is in !TASK_RUNNING. In dvb_frontend_get_event, wait_event_interruptible is
    called; the condition is dvb_frontend_test_event(fepriv,events). In dvb_frontend_test_event,
    down(&fepriv->sem) is called. However, wait_event_interruptible would put the process to sleep, and
    down(&fepriv->sem) may block the process. (CVE-2023-31084)

  - An out-of-bounds write vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited
    to achieve local privilege escalation. The qfq_change_agg() function in net/sched/sch_qfq.c allows an out-
    of-bounds write because lmax is updated according to packet sizes without bounds checks. We recommend
    upgrading past commit 3e337087c3b5805fe0b8a46ba622a962880b5d64. (CVE-2023-3611)

  - A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to
    achieve local privilege escalation. If tcf_change_indev() fails, fw_set_parms() will immediately return an
    error after incrementing or decrementing the reference counter in tcf_bind_filter(). If an attacker can
    control the reference counter and set it to zero, they can cause the reference to be freed, leading to a
    use-after-free vulnerability. We recommend upgrading past commit 0323bce598eea038714f941ce2b22541c46d488f.
    (CVE-2023-3776)

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-6342-2");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:L/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: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-2023-3776");

  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:"2023/03/17");
  script_set_attribute(attribute:"patch_publication_date", value:"2023/09/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/09/08");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:esm");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:esm");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1169-azure");
  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) 2023-2024 Canonical, Inc. / NASL script (C) 2023-2024 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 (! ('16.04' >< os_release || '18.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 16.04 / 18.04', '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 = {
  '16.04': {
    '4.15.0': {
      'azure': '4.15.0-1169'
    }
  },
  '18.04': {
    '4.15.0': {
      'azure': '4.15.0-1169'
    }
  }
};

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-6342-2');
}

if (get_one_kb_item('Host/ksplice/kernel-cves'))
{
  var cve_list = make_list('CVE-2023-2269', 'CVE-2023-2985', 'CVE-2023-3611', 'CVE-2023-3776', 'CVE-2023-20593', 'CVE-2023-31084');
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, 'KSplice hotfix for USN-6342-2');
  }
  else
  {
    extra = extra + ksplice_reporting_text();
  }
}
if (extra) {
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : extra
  );
  exit(0);
}