AlmaLinux 8 : trousers (ALSA-2021:1627)

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Network Security, Inc.
#
# The package checks in this plugin were extracted from
# AlmaLinux Security Advisory ALSA-2021:1627.
##

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

if (description)
{
  script_id(157583);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/11/10");

  script_cve_id("CVE-2020-24330", "CVE-2020-24331", "CVE-2020-24332");
  script_xref(name:"ALSA", value:"2021:1627");
  script_xref(name:"IAVA", value:"2020-A-0453");

  script_name(english:"AlmaLinux 8 : trousers (ALSA-2021:1627)");

  script_set_attribute(attribute:"synopsis", value:
"The remote AlmaLinux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote AlmaLinux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the
ALSA-2021:1627 advisory.

  - An issue was discovered in TrouSerS through 0.3.14. If the tcsd daemon is started with root privileges
    instead of by the tss user, it fails to drop the root gid privilege when no longer needed.
    (CVE-2020-24330)

  - An issue was discovered in TrouSerS through 0.3.14. If the tcsd daemon is started with root privileges,
    the tss user still has read and write access to the /etc/tcsd.conf file (which contains various settings
    related to this daemon). (CVE-2020-24331)

  - An issue was discovered in TrouSerS through 0.3.14. If the tcsd daemon is started with root privileges,
    the creation of the system.data file is prone to symlink attacks. The tss user can be used to create or
    corrupt existing files, which could possibly lead to a DoS attack. (CVE-2020-24332)

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://errata.almalinux.org/8/ALSA-2021-1627.html");
  script_set_attribute(attribute:"solution", value:
"Update the affected trousers, trousers-devel and / or trousers-lib 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:POC/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:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2020-24331");

  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:"2020/08/13");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/05/18");
  script_set_attribute(attribute:"plugin_publication_date", value:"2022/02/09");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alma:linux:trousers");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alma:linux:trousers-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alma:linux:trousers-lib");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alma:linux:8");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Alma Linux 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/AlmaLinux/release", "Host/AlmaLinux/rpm-list", "Host/cpu");

  exit(0);
}


include('audit.inc');
include('global_settings.inc');
include('misc_func.inc');
include('rpm.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var release = get_kb_item('Host/AlmaLinux/release');
if (isnull(release) || 'AlmaLinux' >!< release) audit(AUDIT_OS_NOT, 'AlmaLinux');
var os_ver = pregmatch(pattern: "AlmaLinux release ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'AlmaLinux');
var os_ver = os_ver[1];
if (! preg(pattern:"^8([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, 'AlmaLinux 8.x', 'AlmaLinux ' + os_ver);

if (!get_kb_item('Host/AlmaLinux/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$" && 's390' >!< cpu && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'AlmaLinux', cpu);

var pkgs = [
    {'reference':'trousers-0.3.15-1.el8', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'trousers-devel-0.3.15-1.el8', 'cpu':'i686', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'trousers-devel-0.3.15-1.el8', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'trousers-lib-0.3.15-1.el8', 'cpu':'i686', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'trousers-lib-0.3.15-1.el8', 'cpu':'x86_64', 'release':'8', '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 = 'Alma-' + 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, 'trousers / trousers-devel / trousers-lib');
}