Ubuntu 18.04 LTS : Linux kernel (HWE) vulnerabilities (USN-3930-2)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-3930-2. The text 
# itself is copyright (C) Canonical, Inc. See 
# <http://www.ubuntu.com/usn/>. Ubuntu(R) is a registered 
# trademark of Canonical, Inc.
#

include('compat.inc');

if (description)
{
  script_id(123677);
  script_version("1.11");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/01/09");

  script_cve_id(
    "CVE-2018-19824",
    "CVE-2019-3459",
    "CVE-2019-3460",
    "CVE-2019-6974",
    "CVE-2019-7221",
    "CVE-2019-7222",
    "CVE-2019-7308",
    "CVE-2019-8912",
    "CVE-2019-8956",
    "CVE-2019-8980",
    "CVE-2019-9003",
    "CVE-2019-9162",
    "CVE-2019-9213"
  );
  script_xref(name:"USN", value:"3930-2");

  script_name(english:"Ubuntu 18.04 LTS : Linux kernel (HWE) vulnerabilities (USN-3930-2)");

  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 host has a package installed that is affected by multiple vulnerabilities as referenced in
the USN-3930-2 advisory.

  - In the Linux kernel through 4.19.6, a local user could exploit a use-after-free in the ALSA driver by
    supplying a malicious USB Sound device (with zero interfaces) that is mishandled in usb_audio_probe in
    sound/usb/card.c. (CVE-2018-19824)

  - A heap address information leak while using L2CAP_GET_CONF_OPT was discovered in the Linux kernel before
    5.1-rc1. (CVE-2019-3459)

  - A heap data infoleak in multiple locations including L2CAP_PARSE_CONF_RSP was found in the Linux kernel
    before 5.1-rc1. (CVE-2019-3460)

  - In the Linux kernel before 4.20.8, kvm_ioctl_create_device in virt/kvm/kvm_main.c mishandles reference
    counting because of a race condition, leading to a use-after-free. (CVE-2019-6974)

  - The KVM implementation in the Linux kernel through 4.20.5 has a Use-after-Free. (CVE-2019-7221)

  - The KVM implementation in the Linux kernel through 4.20.5 has an Information Leak. (CVE-2019-7222)

  - kernel/bpf/verifier.c in the Linux kernel before 4.20.6 performs undesirable out-of-bounds speculation on
    pointer arithmetic in various cases, including cases of different branches with different state or limits
    to sanitize, leading to side-channel attacks. (CVE-2019-7308)

  - In the Linux kernel through 4.20.11, af_alg_release() in crypto/af_alg.c neglects to set a NULL value for
    a certain structure member, which leads to a use-after-free in sockfs_setattr. (CVE-2019-8912)

  - In the Linux Kernel before versions 4.20.8 and 4.19.21 a use-after-free error in the sctp_sendmsg()
    function (net/sctp/socket.c) when handling SCTP_SENDALL flag can be exploited to corrupt memory.
    (CVE-2019-8956)

  - A memory leak in the kernel_read_file function in fs/exec.c in the Linux kernel through 4.20.11 allows
    attackers to cause a denial of service (memory consumption) by triggering vfs_read failures.
    (CVE-2019-8980)

  - In the Linux kernel before 4.20.5, attackers can trigger a drivers/char/ipmi/ipmi_msghandler.c use-after-
    free and OOPS by arranging for certain simultaneous execution of the code, as demonstrated by a service
    ipmievd restart loop. (CVE-2019-9003)

  - In the Linux kernel before 4.20.12, net/ipv4/netfilter/nf_nat_snmp_basic_main.c in the SNMP NAT module has
    insufficient ASN.1 length checks (aka an array index error), making out-of-bounds read and write
    operations possible, leading to an OOPS or local privilege escalation. This affects snmp_version and
    snmp_helper. (CVE-2019-9162)

  - In the Linux kernel before 4.20.14, expand_downwards in mm/mmap.c lacks a check for the mmap minimum
    address, which makes it easier for attackers to exploit kernel NULL pointer dereferences on non-SMAP
    platforms. This is related to a capability check for the wrong task. (CVE-2019-9213)

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-3930-2");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:F/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:F/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2019-8956");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2019-6974");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"metasploit_name", value:'Reliable Datagram Sockets (RDS) rds_atomic_free_op NULL pointer dereference Privilege Escalation');
  script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/12/03");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/04/02");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/04/03");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.18.0-1014-azure");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.18.0-17-generic");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.18.0-17-generic-lpae");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.18.0-17-lowlatency");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.18.0-17-snapdragon");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  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) 2019-2024 Canonical, Inc. / NASL script (C) 2019-2024 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)) audit(AUDIT_OS_NOT, 'Ubuntu 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 = {
  '18.04': {
    '4.18.0': {
      'generic': '4.18.0-17',
      'generic-lpae': '4.18.0-17',
      'lowlatency': '4.18.0-17',
      'snapdragon': '4.18.0-17',
      'azure': '4.18.0-1014'
    }
  }
};

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-3930-2');
}

if (get_one_kb_item('Host/ksplice/kernel-cves'))
{
  var cve_list = make_list('CVE-2018-19824', 'CVE-2019-3459', 'CVE-2019-3460', 'CVE-2019-6974', 'CVE-2019-7221', 'CVE-2019-7222', 'CVE-2019-7308', 'CVE-2019-8912', 'CVE-2019-8956', 'CVE-2019-8980', 'CVE-2019-9003', 'CVE-2019-9162', 'CVE-2019-9213');
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, 'KSplice hotfix for USN-3930-2');
  }
  else
  {
    extra = extra + ksplice_reporting_text();
  }
}
if (extra) {
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : extra
  );
  exit(0);
}