F5 Networks BIG-IP : BIG-IP SMTP configuration security exposure (K000156643)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from F5 Networks BIG-IP Solution K000156643.
#
# @NOAGENT@
##

include('compat.inc');

if (description)
{
  script_id(298037);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/08");

  script_name(english:"F5 Networks BIG-IP : BIG-IP SMTP configuration security exposure (K000156643)");

  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 17.1.3.1 / 17.5.1.4 / 21.0.0.1. It is,
therefore, affected by a vulnerability as referenced in the K000156643 advisory.

    An authenticated attacker granted the guest role on a BIG-IP system can modify theSMTP Server Host Nameas
    well as theSMTP Server Port Numbersettings and run the Test Connection feature.This issue occurs when the
    following condition is met:The affected BIG-IP system is configured to send mail through an SMTP server
    and has an existing SMTP configuration on theSystem>Configuration>Device>SMTPpage.Note: The guest role
    does not have the permissions to create a new SMTP configuration on the BIG-IP system.

Tenable has extracted the preceding description block directly from the F5 Networks BIG-IP security advisory.

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/K000156643");
  script_set_attribute(attribute:"solution", value:
"Upgrade to one of the non-vulnerable versions listed in the F5 Solution K000156643.");
  script_set_attribute(attribute:"risk_factor", value:"High");

  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:"2026/02/04");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/02/04");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/02/05");

  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_security_manager");
  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_iapps_lx");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_irules_lx");
  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:/a:f5:big-ip_ssl_orchestrator");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_wan_optimization_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/h:f5:big-ip_protocol_security_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/h:f5:big-ip");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"F5 Networks Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2026 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');
include('local_detection_nix.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 = 'K000156643';
var vmatrix = {
  'AFM': {
    'affected': [
      '21.0.0','17.5.0-17.5.1','17.1.0-17.1.3','16.1.0-16.1.6'
    ],
    'unaffected': [
      '21.0.0.1','17.5.1.4','17.1.3.1'
    ],
  },
  'APM': {
    'affected': [
      '21.0.0','17.5.0-17.5.1','17.1.0-17.1.3','16.1.0-16.1.6'
    ],
    'unaffected': [
      '21.0.0.1','17.5.1.4','17.1.3.1'
    ],
  },
  'ASM': {
    'affected': [
      '21.0.0','17.5.0-17.5.1','17.1.0-17.1.3','16.1.0-16.1.6'
    ],
    'unaffected': [
      '21.0.0.1','17.5.1.4','17.1.3.1'
    ],
  },
  'DNS': {
    'affected': [
      '21.0.0','17.5.0-17.5.1','17.1.0-17.1.3','16.1.0-16.1.6'
    ],
    'unaffected': [
      '21.0.0.1','17.5.1.4','17.1.3.1'
    ],
  },
  'GTM': {
    'affected': [
      '21.0.0','17.5.0-17.5.1','17.1.0-17.1.3','16.1.0-16.1.6'
    ],
    'unaffected': [
      '21.0.0.1','17.5.1.4','17.1.3.1'
    ],
  },
  'LTM': {
    'affected': [
      '21.0.0','17.5.0-17.5.1','17.1.0-17.1.3','16.1.0-16.1.6'
    ],
    'unaffected': [
      '21.0.0.1','17.5.1.4','17.1.3.1'
    ],
  },
  'PEM': {
    'affected': [
      '21.0.0','17.5.0-17.5.1','17.1.0-17.1.3','16.1.0-16.1.6'
    ],
    'unaffected': [
      '21.0.0.1','17.5.1.4','17.1.3.1'
    ],
  },
  'PSM': {
    'affected': [
      '21.0.0','17.5.0-17.5.1','17.1.0-17.1.3','16.1.0-16.1.6'
    ],
    'unaffected': [
      '21.0.0.1','17.5.1.4','17.1.3.1'
    ],
  },
  'SSL-Orchestrator': {
    'affected': [
      '21.0.0','17.5.0-17.5.1','17.1.0-17.1.3','16.1.0-16.1.6'
    ],
    'unaffected': [
      '21.0.0.1','17.5.1.4','17.1.3.1'
    ],
  },
  'WOM': {
    'affected': [
      '21.0.0','17.5.0-17.5.1','17.1.0-17.1.3','16.1.0-16.1.6'
    ],
    'unaffected': [
      '21.0.0.1','17.5.1.4','17.1.3.1'
    ],
  },
  'iAppsLX': {
    'affected': [
      '21.0.0','17.5.0-17.5.1','17.1.0-17.1.3','16.1.0-16.1.6'
    ],
    'unaffected': [
      '21.0.0.1','17.5.1.4','17.1.3.1'
    ],
  },
  'iRulesLX': {
    'affected': [
      '21.0.0','17.5.0-17.5.1','17.1.0-17.1.3','16.1.0-16.1.6'
    ],
    'unaffected': [
      '21.0.0.1','17.5.1.4','17.1.3.1'
    ],
  }
};

function smtp_is_enabled()
{
  # check to see if smtp is enabled on host
  ldnix::init_plugin();
  info_connect(exit_on_fail:TRUE);

  var cmd = "tmsh list sys smtp-server";
  var out = ldnix::run_cmd_template_wrapper(template:cmd);

  # any output indicates SMTP enablement
  if (empty_or_null(out))
    audit(AUDIT_HOST_NOT, 'running an enabled SMTP server');
  else
    return TRUE;
}

if (smtp_is_enabled() && 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_HOLE,
      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');
}