GLSA-202201-01 : Polkit: Local privilege escalation

#%NASL_MIN_LEVEL 70300
#
# (C) Tenable Network Security, Inc.
#
# @NOAGENT@
#
# The descriptive text and package checks in this plugin were
# extracted from Gentoo Linux Security Advisory GLSA 202201-01.
#
# The advisory text is Copyright (C) 2001-2021 Gentoo Foundation, Inc.
# and licensed under the Creative Commons - Attribution / Share Alike
# license. See http://creativecommons.org/licenses/by-sa/3.0/
#

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

if (description)
{
  script_id(157140);
  script_version("1.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/11/17");

  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:"GLSA-202201-01 : Polkit: Local privilege escalation");

  script_set_attribute(attribute:"synopsis", value:
"");
  script_set_attribute(attribute:"description", value:
"The remote host is affected by the vulnerability described in GLSA-202201-01 (Polkit: Local privilege escalation)

  - 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://security.gentoo.org/glsa/202201-01");
  script_set_attribute(attribute:"see_also", value:"https://bugs.gentoo.org/show_bug.cgi?id=832057");
  script_set_attribute(attribute:"solution", value:
"Upgrade Polkit to a patched version.

			emerge --ask --verbose >=sys-auth/polkit-0.120-r2");
  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:"2022/01/27");
  script_set_attribute(attribute:"plugin_publication_date", value:"2022/01/27");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:gentoo:linux:polkit");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Gentoo 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/Gentoo/release", "Host/Gentoo/qpkg-list");

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

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Gentoo/release")) audit(AUDIT_OS_NOT, "Gentoo");
if (!get_kb_item("Host/Gentoo/qpkg-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

var flag = 0;

var packages = [
  {
    'name' : "sys-auth/polkit",
    'unaffected' : make_list("ge 0.120-r2"),
    'vulnerable' : make_list("lt 0.120-r2")
  }
];

foreach package( packages ) {
  if (isnull(package['unaffected'])) package['unaffected'] = make_list();
  if (isnull(package['vulnerable'])) package['vulnerable'] = make_list();
  if (qpkg_check(package: package['name'] , unaffected: package['unaffected'], vulnerable: package['vulnerable'])) flag++;
}


if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : qpkg_report_get()
  );
  exit(0);
}
else
{
  var tested = qpkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "Polkit");
}