RHEL 7 : systemd (Unpatched Vulnerability)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Red Hat Security Advisory systemd. The text
# itself is copyright (C) Red Hat, Inc.
##

include('compat.inc');

if (description)
{
  script_id(195801);
  script_version("1.0");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/05/11");

  script_cve_id(
    "CVE-2017-18078",
    "CVE-2018-6954",
    "CVE-2019-3842",
    "CVE-2020-13529",
    "CVE-2020-13776",
    "CVE-2021-3997",
    "CVE-2022-3821",
    "CVE-2022-4415",
    "CVE-2022-45873"
  );

  script_name(english:"RHEL 7 : systemd (Unpatched Vulnerability)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Red Hat 7 host is affected by multiple vulnerabilities that will not be patched.");
  script_set_attribute(attribute:"description", value:
"The remote Redhat Enterprise Linux 7 host has one or more packages installed that are affected by multiple
vulnerabilities that have been acknowledged by the vendor but will not be patched.

  - systemd: Mishandled symlinks in systemd-tmpfiles allows local users to obtain ownership of arbitrary files
    (CVE-2018-6954)

  - systemd-tmpfiles in systemd before 237 attempts to support ownership/permission changes on hardlinked
    files even if the fs.protected_hardlinks sysctl is turned off, which allows local users to bypass intended
    access restrictions via vectors involving a hard link to a file for which the user lacks write access, as
    demonstrated by changing the ownership of the /etc/passwd file. (CVE-2017-18078)

  - In systemd before v242-rc4, it was discovered that pam_systemd does not properly sanitize the environment
    before using the XDG_SEAT variable. It is possible for an attacker, in some particular configurations, to
    set a XDG_SEAT environment variable which allows for commands to be checked against polkit policies using
    the allow_active element rather than allow_any. (CVE-2019-3842)

  - An exploitable denial-of-service vulnerability exists in Systemd 245. A specially crafted DHCP FORCERENEW
    packet can cause a server running the DHCP client to be vulnerable to a DHCP ACK spoofing attack. An
    attacker can forge a pair of FORCERENEW and DCHP ACK packets to reconfigure the server. (CVE-2020-13529)

  - systemd through v245 mishandles numerical usernames such as ones composed of decimal digits or 0x followed
    by hex digits, as demonstrated by use of root privileges when privileges of the 0x0 user account were
    intended. NOTE: this issue exists because of an incomplete fix for CVE-2017-1000082. (CVE-2020-13776)

  - A flaw was found in systemd. An uncontrolled recursion in systemd-tmpfiles may lead to a denial of service
    at boot time when too many nested directories are created in /tmp. (CVE-2021-3997)

  - An off-by-one Error issue was discovered in Systemd in format_timespan() function of time-util.c. An
    attacker could supply specific values for time and accuracy that leads to buffer overrun in
    format_timespan(), leading to a Denial of Service. (CVE-2022-3821)

  - A vulnerability was found in systemd. This security flaw can cause a local information leak due to
    systemd-coredump not respecting the fs.suid_dumpable kernel setting. (CVE-2022-4415)

  - systemd 250 and 251 allows local users to achieve a systemd-coredump deadlock by triggering a crash that
    has a long backtrace. This occurs in parse_elf_object in shared/elf-util.c. The exploitation methodology
    is to crash a binary calling the same function recursively, and put it in a deeply nested directory to
    make its backtrace large enough to cause the deadlock. This must be done 16 times when MaxConnections=16
    is set for the systemd/units/systemd-coredump.socket file. (CVE-2022-45873)

Note that Nessus has not tested for these issues but has instead relied on the package manager's report that the package
is installed.");
  script_set_attribute(attribute:"solution", value:
"The vendor has acknowledged the vulnerabilities but no solution has been provided. Refer to the vendor for remediation
guidance.");
  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-2018-6954");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"vendor_unpatched", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/01/25");
  script_set_attribute(attribute:"plugin_publication_date", value:"2024/05/11");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:7");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:NetworkManager");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:systemd");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

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

  exit(0);
}


include('rpm.inc');
include('rhel.inc');

if (!get_kb_item("global_settings/vendor_unpatched"))
exit(0, "Unpatched Vulnerabilities Detection not active.");

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_release = get_kb_item('Host/RedHat/release');
if (isnull(os_release) || 'Red Hat' >!< os_release) audit(AUDIT_OS_NOT, 'Red Hat');
var os_ver = pregmatch(pattern: "Red Hat Enterprise Linux.*release ([0-9]+(\.[0-9]+)?)", string:os_release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'Red Hat');
os_ver = os_ver[1];
if (!rhel_check_release(operator: 'ge', os_version: os_ver, rhel_version: '7')) audit(AUDIT_OS_NOT, 'Red Hat 7.x', 'Red Hat ' + os_ver);

if (!get_kb_item('Host/RedHat/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 && 'ppc' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Red Hat', cpu);

var constraints = [
  {
    'pkgs': [
      {'reference':'NetworkManager', 'release':'7', 'rpm_spec_vers_cmp':TRUE, 'unpatched_pkg':'NetworkManager', 'cves':['CVE-2020-13529', 'CVE-2022-4415', 'CVE-2022-45873']},
      {'reference':'systemd', 'release':'7', 'rpm_spec_vers_cmp':TRUE, 'unpatched_pkg':'systemd'}
    ]
  }
];


var flag = 0;
foreach var constraint_array ( constraints ) {
  var repo_relative_urls = NULL;
  var enterprise_linux_flag = rhel_repo_urls_has_content_dist_rhel(repo_urls:repo_relative_urls);
  foreach var pkg ( constraint_array['pkgs'] ) {
    var unpatched_pkg = NULL;
    var _release = NULL;
    var sp = NULL;
    var el_string = NULL;
    var rpm_spec_vers_cmp = NULL;
    var exists_check = NULL;
    var cves = NULL;
    if (!empty_or_null(pkg['unpatched_pkg'])) unpatched_pkg = pkg['unpatched_pkg'];
    if (!empty_or_null(pkg['release'])) _release = 'RHEL' + pkg['release'];
    if (!empty_or_null(pkg['sp'])) sp = pkg['sp'];
    if (!empty_or_null(pkg['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = pkg['rpm_spec_vers_cmp'];
    if (!empty_or_null(pkg['exists_check'])) exists_check = pkg['exists_check'];
    if (!empty_or_null(pkg['cves'])) cves = pkg['cves'];
    if (unpatched_pkg &&
        _release &&
        (!exists_check || rpm_exists(release:_release, rpm:exists_check)) &&
        unpatched_package_exists(release:_release, package:unpatched_pkg, cves: cves)) flag++;
  }
}

if (flag)
{
  var extra = NULL;
  security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      extra      : unpatched_packages_report()
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'NetworkManager / systemd');
}