Ubuntu 16.04 ESM / 18.04 LTS : Linux kernel vulnerabilities (USN-4979-1)

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-4979-1. The text
# itself is copyright (C) Canonical, Inc. See
# <https://ubuntu.com/security/notices>. Ubuntu(R) is a registered
# trademark of Canonical, Inc.
##

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(150155);
  script_version("1.8");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/01/09");

  script_cve_id(
    "CVE-2020-25670",
    "CVE-2020-25671",
    "CVE-2020-25672",
    "CVE-2020-25673",
    "CVE-2021-3428",
    "CVE-2021-3483",
    "CVE-2021-28660",
    "CVE-2021-28964",
    "CVE-2021-28971",
    "CVE-2021-28972",
    "CVE-2021-29647",
    "CVE-2021-31916",
    "CVE-2021-33033"
  );
  script_xref(name:"USN", value:"4979-1");

  script_name(english:"Ubuntu 16.04 ESM / 18.04 LTS : Linux kernel vulnerabilities (USN-4979-1)");

  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 LTS host has a package installed that is affected by multiple vulnerabilities as
referenced in the USN-4979-1 advisory.

  - A vulnerability was found in Linux Kernel where refcount leak in llcp_sock_bind() causing use-after-free
    which might lead to privilege escalations. (CVE-2020-25670)

  - A vulnerability was found in Linux Kernel, where a refcount leak in llcp_sock_connect() causing use-after-
    free which might lead to privilege escalations. (CVE-2020-25671)

  - A memory leak vulnerability was found in Linux kernel in llcp_sock_connect (CVE-2020-25672)

  - A vulnerability was found in Linux kernel where non-blocking socket in llcp_sock_connect() leads to leak
    and eventually hanging-up the system. (CVE-2020-25673)

  - rtw_wx_set_scan in drivers/staging/rtl8188eu/os_dep/ioctl_linux.c in the Linux kernel through 5.11.6
    allows writing beyond the end of the ->ssid[] array. NOTE: from the perspective of kernel.org releases,
    CVE IDs are not normally used for drivers/staging/* (unfinished work); however, system integrators may
    have situations in which a drivers/staging issue is relevant to their own customer base. (CVE-2021-28660)

  - A race condition was discovered in get_old_root in fs/btrfs/ctree.c in the Linux kernel through 5.11.8. It
    allows attackers to cause a denial of service (BUG) because of a lack of locking on an extent buffer
    before a cloning operation, aka CID-dbcc7d57bffc. (CVE-2021-28964)

  - In intel_pmu_drain_pebs_nhm in arch/x86/events/intel/ds.c in the Linux kernel through 5.11.8 on some
    Haswell CPUs, userspace applications (such as perf-fuzzer) can cause a system crash because the PEBS
    status in a PEBS record is mishandled, aka CID-d88d05a9e0b6. (CVE-2021-28971)

  - In drivers/pci/hotplug/rpadlpar_sysfs.c in the Linux kernel through 5.11.8, the RPA PCI Hotplug driver has
    a user-tolerable buffer overflow when writing a new device name to the driver from userspace, allowing
    userspace to write data to the kernel stack frame directly. This occurs because add_slot_store and
    remove_slot_store mishandle drc_name '\0' termination, aka CID-cc7a0bb058b8. (CVE-2021-28972)

  - An issue was discovered in the Linux kernel before 5.11.11. qrtr_recvmsg in net/qrtr/qrtr.c allows
    attackers to obtain sensitive information from kernel memory because of a partially uninitialized data
    structure, aka CID-50535249f624. (CVE-2021-29647)

  - An out-of-bounds (OOB) memory write flaw was found in list_devices in drivers/md/dm-ioctl.c in the Multi-
    device driver module in the Linux kernel before 5.12. A bound check failure allows an attacker with
    special user (CAP_SYS_ADMIN) privilege to gain access to out-of-bounds memory leading to a system crash or
    a leak of internal kernel information. The highest threat from this vulnerability is to system
    availability. (CVE-2021-31916)

  - The Linux kernel before 5.11.14 has a use-after-free in cipso_v4_genopt in net/ipv4/cipso_ipv4.c because
    the CIPSO and CALIPSO refcounting for the DOI definitions is mishandled, aka CID-ad5d07f4a9cd. This leads
    to writing an arbitrary value. (CVE-2021-33033)

  - A flaw was found in the Linux kernel. A denial of service problem is identified if an extent tree is
    corrupted in a crafted ext4 filesystem in fs/ext4/extents.c in ext4_es_cache_extent. Fabricating an
    integer overflow, A local attacker with a special user privilege may cause a system crash problem which
    can lead to an availability threat. (CVE-2021-3428)

  - A flaw was found in the Nosy driver in the Linux kernel. This issue allows a device to be inserted twice
    into a doubly-linked list, leading to a use-after-free when one of these devices is removed. The highest
    threat from this vulnerability is to confidentiality, integrity, as well as system availability. Versions
    before kernel 5.12-rc6 are affected (CVE-2021-3483)

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-4979-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:A/AC:L/Au:N/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:A/AC:L/PR:N/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-2021-28660");

  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:"2021/03/17");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/06/03");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/06/03");

  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:-:lts");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1072-oracle");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1086-raspi2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1092-kvm");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1100-gcp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1103-aws");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1103-snapdragon");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1115-azure");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-144-generic");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-144-generic-lpae");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-144-lowlatency");
  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) 2021-2024 Canonical, Inc. / NASL script (C) 2021-2024 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': {
      'generic': '4.15.0-144',
      'lowlatency': '4.15.0-144',
      'oracle': '4.15.0-1072',
      'gcp': '4.15.0-1100',
      'aws': '4.15.0-1103',
      'azure': '4.15.0-1115'
    }
  },
  '18.04': {
    '4.15.0': {
      'generic': '4.15.0-144',
      'generic-lpae': '4.15.0-144',
      'lowlatency': '4.15.0-144',
      'oracle': '4.15.0-1072',
      'raspi2': '4.15.0-1086',
      'kvm': '4.15.0-1092',
      'gcp': '4.15.0-1100',
      'snapdragon': '4.15.0-1103',
      'azure': '4.15.0-1115'
    }
  }
};

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-4979-1');
}

if (get_one_kb_item('Host/ksplice/kernel-cves'))
{
  var cve_list = make_list('CVE-2020-25670', 'CVE-2020-25671', 'CVE-2020-25672', 'CVE-2020-25673', 'CVE-2021-3428', 'CVE-2021-3483', 'CVE-2021-28660', 'CVE-2021-28964', 'CVE-2021-28971', 'CVE-2021-28972', 'CVE-2021-29647', 'CVE-2021-31916', 'CVE-2021-33033');
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, 'KSplice hotfix for USN-4979-1');
  }
  else
  {
    extra = extra + ksplice_reporting_text();
  }
}
if (extra) {
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : extra
  );
  exit(0);
}