Alibaba Cloud Linux 3 : 0004: polkit (ALINUX3-SA-2022:0004)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The package checks in this plugin were extracted from
# Alibaba Cloud Linux Security Advisory ALINUX3-SA-2022:0004.
##

include('compat.inc');

if (description)
{
  script_id(236558);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/05/14");

  script_cve_id("CVE-2019-6133", "CVE-2021-4034");
  script_xref(name:"CISA-KNOWN-EXPLOITED", value:"2022/07/18");

  script_name(english:"Alibaba Cloud Linux 3 : 0004: polkit (ALINUX3-SA-2022:0004)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Alibaba Cloud Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Alibaba Cloud Linux 3 host has packages installed that are affected by multiple vulnerabilities as referenced
in the ALINUX3-SA-2022:0004 advisory.

    Package updates are available for Alibaba Cloud Linux 3 that fix the following vulnerabilities:

    CVE-2019-6133:
    In PolicyKit (aka polkit) 0.115, the start time protection mechanism can be bypassed because fork() is
    not atomic, and therefore authorization decisions are improperly cached. This is related to lack of uid
    checking in polkitbackend/polkitbackendinteractiveauthority.c.

    CVE-2021-4034:
    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.

Tenable has extracted the preceding description block directly from the Alibaba Cloud Linux security advisory.

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:"http://mirrors.aliyun.com/alinux/3/cve/alinux3-sa-20220004.xml");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  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:"vuln_publication_date", value:"2019/01/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2022/01/26");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/05/14");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:polkit");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:polkit-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:polkit-debugsource");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:polkit-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:polkit-docs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:polkit-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:polkit-libs-debuginfo");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alibabacloud:alibaba_cloud_linux_3");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Alibaba Cloud Linux Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2025 and is owned by Tenable, Inc. or an Affiliate thereof.");

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

  exit(0);
}


include('rpm.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_release = get_kb_item('Host/Alibaba/release');
if (isnull(os_release) || 'Alibaba Cloud Linux' >!< os_release) audit(AUDIT_OS_NOT, 'Alibaba Cloud Linux');
var os_ver = pregmatch(pattern: "Alibaba Cloud Linux release ([0-9]+(\.[0-9]+)?)", string:os_release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'Alibaba Cloud Linux');
os_ver = os_ver[1];
if (! preg(pattern:"^3([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, 'Alibaba Cloud Linux 3.x', 'Alibaba Cloud Linux ' + os_ver);

if (!get_kb_item('Host/Alibaba/rpm-list')) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('aarch64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Alibaba Cloud Linux', cpu);

var pkgs = [
    {'reference':'polkit-0.115-13.al8.1', 'cpu':'aarch64', 'release':'3', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
    {'reference':'polkit-0.115-13.al8.1', 'cpu':'x86_64', 'release':'3', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
    {'reference':'polkit-debuginfo-0.115-13.al8.1', 'cpu':'aarch64', 'release':'3', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
    {'reference':'polkit-debuginfo-0.115-13.al8.1', 'cpu':'x86_64', 'release':'3', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
    {'reference':'polkit-debugsource-0.115-13.al8.1', 'cpu':'aarch64', 'release':'3', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
    {'reference':'polkit-debugsource-0.115-13.al8.1', 'cpu':'x86_64', 'release':'3', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
    {'reference':'polkit-devel-0.115-13.al8.1', 'cpu':'aarch64', 'release':'3', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
    {'reference':'polkit-devel-0.115-13.al8.1', 'cpu':'x86_64', 'release':'3', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
    {'reference':'polkit-docs-0.115-13.al8.1', 'release':'3', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
    {'reference':'polkit-libs-0.115-13.al8.1', 'cpu':'aarch64', 'release':'3', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
    {'reference':'polkit-libs-0.115-13.al8.1', 'cpu':'x86_64', 'release':'3', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
    {'reference':'polkit-libs-debuginfo-0.115-13.al8.1', 'cpu':'aarch64', 'release':'3', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
    {'reference':'polkit-libs-debuginfo-0.115-13.al8.1', 'cpu':'x86_64', 'release':'3', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'}
];

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;
  var cves = NULL;
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (!empty_or_null(package_array['release'])) _release = 'Alibaba Linux ' + 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 (!empty_or_null(package_array['cves'])) cves = package_array['cves'];
  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, cves:cves)) 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 / polkit-debuginfo / polkit-debugsource / polkit-devel / etc');
}