SUSE SLED15 / SLES15 Security Update : openssh (SUSE-SU-2021:3950-1)

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable, Inc.
#
# The package checks in this plugin were extracted from
# SUSE update advisory SUSE-SU-2021:3950-1. The text itself
# is copyright (C) SUSE.
##

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

if (description)
{
  script_id(155896);
  script_version("1.5");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/07/13");

  script_cve_id("CVE-2021-41617");
  script_xref(name:"SuSE", value:"SUSE-SU-2021:3950-1");
  script_xref(name:"IAVA", value:"2021-A-0474-S");

  script_name(english:"SUSE SLED15 / SLES15 Security Update : openssh (SUSE-SU-2021:3950-1)");

  script_set_attribute(attribute:"synopsis", value:
"The remote SUSE host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The remote SUSE Linux SLED15 / SLES15 host has packages installed that are affected by a vulnerability as referenced in
the SUSE-SU-2021:3950-1 advisory.

  - sshd in OpenSSH 6.2 through 8.x before 8.8, when certain non-default configurations are used, allows
    privilege escalation because supplemental groups are not initialized as expected. Helper programs for
    AuthorizedKeysCommand and AuthorizedPrincipalsCommand may run with privileges associated with group
    memberships of the sshd process, if the configuration specifies running the command as a different user.
    (CVE-2021-41617)

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://bugzilla.suse.com/1190975");
  script_set_attribute(attribute:"see_also", value:"https://www.suse.com/security/cve/CVE-2021-41617");
  # https://lists.suse.com/pipermail/sle-security-updates/2021-December/009857.html
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?282e2402");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-41617");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2021/09/26");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/12/06");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/12/07");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:openssh");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:openssh-askpass-gnome");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:openssh-clients");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:openssh-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:openssh-fips");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:openssh-helpers");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:openssh-server");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:novell:suse_linux:15");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2021-2023 and is owned by Tenable, Inc. or an Affiliate thereof.");

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

  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/SuSE/release");
if (isnull(os_release) || os_release !~ "^(SLED|SLES)") audit(AUDIT_OS_NOT, "SUSE");
var os_ver = pregmatch(pattern: "^(SLE(S|D)\d+)", string:os_release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'SUSE');
os_ver = os_ver[1];
if (! preg(pattern:"^(SLED15|SLES15)$", string:os_ver)) audit(AUDIT_OS_NOT, 'SUSE SLED15 / SLES15', 'SUSE (' + os_ver + ')');

if (!get_kb_item("Host/SuSE/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, 'SUSE (' + os_ver + ')', cpu);

var service_pack = get_kb_item("Host/SuSE/patchlevel");
if (isnull(service_pack)) service_pack = "0";
if (os_ver == "SLED15" && (! preg(pattern:"^(3)$", string:service_pack))) audit(AUDIT_OS_NOT, "SLED15 SP3", os_ver + " SP" + service_pack);
if (os_ver == "SLES15" && (! preg(pattern:"^(3)$", string:service_pack))) audit(AUDIT_OS_NOT, "SLES15 SP3", os_ver + " SP" + service_pack);

var pkgs = [
    {'reference':'openssh-8.4p1-3.6.1', 'sp':'3', 'release':'SLED15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-basesystem-release-15.3']},
    {'reference':'openssh-8.4p1-3.6.1', 'sp':'3', 'release':'SLES15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-basesystem-release-15.3']},
    {'reference':'openssh-clients-8.4p1-3.6.1', 'sp':'3', 'release':'SLED15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-basesystem-release-15.3']},
    {'reference':'openssh-clients-8.4p1-3.6.1', 'sp':'3', 'release':'SLES15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-basesystem-release-15.3']},
    {'reference':'openssh-common-8.4p1-3.6.1', 'sp':'3', 'release':'SLED15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-basesystem-release-15.3']},
    {'reference':'openssh-common-8.4p1-3.6.1', 'sp':'3', 'release':'SLES15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-basesystem-release-15.3']},
    {'reference':'openssh-fips-8.4p1-3.6.1', 'sp':'3', 'release':'SLED15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-basesystem-release-15.3']},
    {'reference':'openssh-fips-8.4p1-3.6.1', 'sp':'3', 'release':'SLES15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-basesystem-release-15.3', 'sle-module-server-applications-release-15.3']},
    {'reference':'openssh-helpers-8.4p1-3.6.1', 'sp':'3', 'release':'SLED15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-basesystem-release-15.3']},
    {'reference':'openssh-helpers-8.4p1-3.6.1', 'sp':'3', 'release':'SLES15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-basesystem-release-15.3']},
    {'reference':'openssh-server-8.4p1-3.6.1', 'sp':'3', 'release':'SLED15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-basesystem-release-15.3']},
    {'reference':'openssh-server-8.4p1-3.6.1', 'sp':'3', 'release':'SLES15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-basesystem-release-15.3']},
    {'reference':'openssh-askpass-gnome-8.4p1-3.6.1', 'sp':'3', 'release':'SLED15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-desktop-applications-release-15.3']},
    {'reference':'openssh-askpass-gnome-8.4p1-3.6.1', 'sp':'3', 'release':'SLES15', 'rpm_spec_vers_cmp':TRUE, 'allowmaj':TRUE, 'exists_check':['sle-module-desktop-applications-release-15.3']}
];

var ltss_caveat_required = FALSE;
var flag = 0;
foreach var package_array ( pkgs ) {
  var reference = NULL;
  var _release = NULL;
  var sp = NULL;
  var _cpu = NULL;
  var exists_check = NULL;
  var rpm_spec_vers_cmp = NULL;
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (!empty_or_null(package_array['release'])) _release = 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['exists_check'])) exists_check = package_array['exists_check'];
  if (!empty_or_null(package_array['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = package_array['rpm_spec_vers_cmp'];
  if (reference && _release) {
    if (exists_check) {
      var check_flag = 0;
      foreach var check (exists_check) {
        if (!rpm_exists(release:_release, rpm:check)) continue;
        check_flag++;
      }
      if (!check_flag) continue;
    }
    if (rpm_check(release:_release, sp:sp, cpu:_cpu, reference:reference, rpm_spec_vers_cmp:rpm_spec_vers_cmp)) flag++;
  }
}

if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      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, 'openssh / openssh-askpass-gnome / openssh-clients / openssh-common / etc');
}