OracleVM 3.4 : polkit (OVMSA-2022-0006)

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Network Security, Inc.
#
# The package checks in this plugin were
# extracted from OracleVM Security Advisory OVMSA-2022-0006.
##

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

if (description)
{
  script_id(158121);
  script_version("1.8");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/01/16");

  script_cve_id("CVE-2021-4034");
  script_xref(name:"IAVA", value:"2022-A-0055");
  script_xref(name:"CISA-KNOWN-EXPLOITED", value:"2022/07/18");

  script_name(english:"OracleVM 3.4 : polkit (OVMSA-2022-0006)");

  script_set_attribute(attribute:"synopsis", value:
"The remote OracleVM host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote OracleVM system is missing necessary patches to address security updates:

  - A local privilege escalation vulnerability was found on polkit's pkexec utility. The pkexec application is
    a setuid tool designed to allow unprivileged users to run commands as privileged users according
    predefined policies. The current version of pkexec doesn't handle the calling parameters count correctly
    and ends trying to execute environment variables as commands. An attacker can leverage this by crafting
    environment variables in such a way it'll induce pkexec to execute arbitrary code. When successfully
    executed the attack can cause a local privilege escalation given unprivileged users administrative rights
    on the target machine. (CVE-2021-4034)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://linux.oracle.com/cve/CVE-2021-4034.html");
  script_set_attribute(attribute:"see_also", value:"https://linux.oracle.com/errata/OVMSA-2022-0006.html");
  script_set_attribute(attribute:"solution", value:
"Update the affected polkit 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:H/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:H/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-4034");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"exploit_framework_core", value:"true");
  script_set_attribute(attribute:"exploited_by_malware", value:"true");
  script_set_attribute(attribute:"metasploit_name", value:'Local Privilege Escalation in polkits pkexec');
  script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");
  script_set_attribute(attribute:"exploit_framework_canvas", value:"true");
  script_set_attribute(attribute:"canvas_package", value:"CANVAS");

  script_set_attribute(attribute:"vuln_publication_date", value:"2022/01/25");
  script_set_attribute(attribute:"patch_publication_date", value:"2022/01/28");
  script_set_attribute(attribute:"plugin_publication_date", value:"2022/02/17");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:vm:polkit");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:oracle:vm_server:3.4");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2022-2023 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/OracleVM/release", "Host/OracleVM/rpm-list");

  exit(0);
}
include("audit.inc");
include("global_settings.inc");
include("rpm.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var release = get_kb_item("Host/OracleVM/release");
if (isnull(release) || "OVS" >!< release) audit(AUDIT_OS_NOT, "OracleVM");
if (! preg(pattern:"^OVS" + "3\.4" + "(\.[0-9]|$)", string:release)) audit(AUDIT_OS_NOT, "OracleVM 3.4", "OracleVM " + release);
if (!get_kb_item("Host/OracleVM/rpm-list")) 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$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "OracleVM", cpu);
if ("x86_64" >!< cpu) audit(AUDIT_ARCH_NOT, "x86_64", cpu);

var pkgs = [
    {'reference':'polkit-0.96-11.0.1.el6_10.1', 'cpu':'x86_64', 'release':'3.4', 'rpm_spec_vers_cmp':TRUE}
];

var flag = 0;
foreach var package_array ( pkgs ) {
  var reference = NULL;
  var release = NULL;
  var sp = NULL;
  var cpu = NULL;
  var el_string = NULL;
  var rpm_spec_vers_cmp = NULL;
  var epoch = NULL;
  var allowmaj = NULL;
  var exists_check = NULL;
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (!empty_or_null(package_array['release'])) release = 'OVS' + package_array['release'];
  if (!empty_or_null(package_array['sp'])) sp = package_array['sp'];
  if (!empty_or_null(package_array['cpu'])) cpu = package_array['cpu'];
  if (!empty_or_null(package_array['el_string'])) el_string = package_array['el_string'];
  if (!empty_or_null(package_array['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = package_array['rpm_spec_vers_cmp'];
  if (!empty_or_null(package_array['epoch'])) epoch = package_array['epoch'];
  if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
  if (!empty_or_null(package_array['exists_check'])) exists_check = package_array['exists_check'];
  if (reference && release && (!exists_check || rpm_exists(release:release, rpm:exists_check))) {
    if (rpm_check(release:release, sp:sp, cpu:cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj)) flag++;
  }
}

if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'polkit');
}