F5 Networks BIG-IP : BIG-IP SNAT vulnerability (K31934524)

##
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from F5 Networks BIG-IP Solution K31934524.
#
# @NOAGENT@
##

include('compat.inc');

if (description)
{
  script_id(147631);
  script_version("1.7");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/11/02");

  script_cve_id("CVE-2021-22998");

  script_name(english:"F5 Networks BIG-IP : BIG-IP SNAT vulnerability (K31934524)");

  script_set_attribute(attribute:"synopsis", value:
"The remote device is missing a vendor-supplied security patch.");
  script_set_attribute(attribute:"description", value:
"The version of F5 Networks BIG-IP installed on the remote host is prior to 11.6.5.3 / 12.1.5.3 / 13.1.3.6 / 14.1.4 /
15.1.2.1 / 16.0.1.1 / 16.1.0. It is, therefore, affected by a vulnerability as referenced in the K31934524 advisory.

  - On BIG-IP versions 16.0.x before 16.0.1.1, 15.1.x before 15.1.2.1, 14.1.x before 14.1.4, 13.1.x before
    13.1.3.6, 12.1.x before 12.1.5.3, and 11.6.x before 11.6.5.3, SYN flood protection thresholds are not
    enforced in secure network address translation (SNAT) listeners. Note: Software versions which have
    reached End of Software Development (EoSD) are not evaluated. (CVE-2021-22998)

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://my.f5.com/manage/s/article/K31934524");
  script_set_attribute(attribute:"solution", value:
"Upgrade to one of the non-vulnerable versions listed in the F5 Solution K31934524.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-22998");

  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:"2021/03/31");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/03/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/03/10");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_access_policy_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_advanced_firewall_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_application_acceleration_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_application_security_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_application_visibility_and_reporting");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_domain_name_system");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_global_traffic_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_link_controller");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_local_traffic_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_policy_enforcement_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/h:f5:big-ip");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"F5 Networks 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("f5_bigip_detect.nbin");
  script_require_keys("Host/local_checks_enabled", "Host/BIG-IP/hotfix", "Host/BIG-IP/modules", "Host/BIG-IP/version");

  exit(0);
}


include('f5_func.inc');

if ( ! get_kb_item('Host/local_checks_enabled') ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var version = get_kb_item('Host/BIG-IP/version');
if ( ! version ) audit(AUDIT_OS_NOT, 'F5 Networks BIG-IP');
if ( isnull(get_kb_item('Host/BIG-IP/hotfix')) ) audit(AUDIT_KB_MISSING, 'Host/BIG-IP/hotfix');
if ( ! get_kb_item('Host/BIG-IP/modules') ) audit(AUDIT_KB_MISSING, 'Host/BIG-IP/modules');

var sol = 'K31934524';
var vmatrix = {
  'AFM': {
    'affected': [
      '16.0.0-16.0.1','15.0.0-15.1.2','14.1.0-14.1.3','13.1.0-13.1.3','12.1.0-12.1.5','11.6.1-11.6.5'
    ],
    'unaffected': [
      '16.1.0','16.0.1.1','15.1.2.1','14.1.4','13.1.3.6','12.1.5.3','11.6.5.3'
    ],
  },
  'AM': {
    'affected': [
      '16.0.0-16.0.1','15.0.0-15.1.2','14.1.0-14.1.3','13.1.0-13.1.3','12.1.0-12.1.5','11.6.1-11.6.5'
    ],
    'unaffected': [
      '16.1.0','16.0.1.1','15.1.2.1','14.1.4','13.1.3.6','12.1.5.3','11.6.5.3'
    ],
  },
  'APM': {
    'affected': [
      '16.0.0-16.0.1','15.0.0-15.1.2','14.1.0-14.1.3','13.1.0-13.1.3','12.1.0-12.1.5','11.6.1-11.6.5'
    ],
    'unaffected': [
      '16.1.0','16.0.1.1','15.1.2.1','14.1.4','13.1.3.6','12.1.5.3','11.6.5.3'
    ],
  },
  'ASM': {
    'affected': [
      '16.0.0-16.0.1','15.0.0-15.1.2','14.1.0-14.1.3','13.1.0-13.1.3','12.1.0-12.1.5','11.6.1-11.6.5'
    ],
    'unaffected': [
      '16.1.0','16.0.1.1','15.1.2.1','14.1.4','13.1.3.6','12.1.5.3','11.6.5.3'
    ],
  },
  'AVR': {
    'affected': [
      '16.0.0-16.0.1','15.0.0-15.1.2','14.1.0-14.1.3','13.1.0-13.1.3','12.1.0-12.1.5','11.6.1-11.6.5'
    ],
    'unaffected': [
      '16.1.0','16.0.1.1','15.1.2.1','14.1.4','13.1.3.6','12.1.5.3','11.6.5.3'
    ],
  },
  'DNS': {
    'affected': [
      '16.0.0-16.0.1','15.0.0-15.1.2','14.1.0-14.1.3','13.1.0-13.1.3','12.1.0-12.1.5','11.6.1-11.6.5'
    ],
    'unaffected': [
      '16.1.0','16.0.1.1','15.1.2.1','14.1.4','13.1.3.6','12.1.5.3','11.6.5.3'
    ],
  },
  'GTM': {
    'affected': [
      '16.0.0-16.0.1','15.0.0-15.1.2','14.1.0-14.1.3','13.1.0-13.1.3','12.1.0-12.1.5','11.6.1-11.6.5'
    ],
    'unaffected': [
      '16.1.0','16.0.1.1','15.1.2.1','14.1.4','13.1.3.6','12.1.5.3','11.6.5.3'
    ],
  },
  'LC': {
    'affected': [
      '16.0.0-16.0.1','15.0.0-15.1.2','14.1.0-14.1.3','13.1.0-13.1.3','12.1.0-12.1.5','11.6.1-11.6.5'
    ],
    'unaffected': [
      '16.1.0','16.0.1.1','15.1.2.1','14.1.4','13.1.3.6','12.1.5.3','11.6.5.3'
    ],
  },
  'LTM': {
    'affected': [
      '16.0.0-16.0.1','15.0.0-15.1.2','14.1.0-14.1.3','13.1.0-13.1.3','12.1.0-12.1.5','11.6.1-11.6.5'
    ],
    'unaffected': [
      '16.1.0','16.0.1.1','15.1.2.1','14.1.4','13.1.3.6','12.1.5.3','11.6.5.3'
    ],
  },
  'PEM': {
    'affected': [
      '16.0.0-16.0.1','15.0.0-15.1.2','14.1.0-14.1.3','13.1.0-13.1.3','12.1.0-12.1.5','11.6.1-11.6.5'
    ],
    'unaffected': [
      '16.1.0','16.0.1.1','15.1.2.1','14.1.4','13.1.3.6','12.1.5.3','11.6.5.3'
    ],
  }
};

if (bigip_is_affected(vmatrix:vmatrix, sol:sol))
{
  var extra = NULL;
  if (report_verbosity > 0) extra = bigip_report_get();
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : extra
  );
}
else
{
  var tested = bigip_get_tested_modules();
  var audit_extra = 'For BIG-IP module(s) ' + tested + ',';
  if (tested) audit(AUDIT_INST_VER_NOT_VULN, audit_extra, version);
  else audit(AUDIT_HOST_NOT, 'running any of the affected modules');
}