Cisco Nexus 9000 Series Fabric Switches ACI Mode Border Leaf Endpoint Learning (CVE-2019-1977)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(501402);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/07/26");

  script_cve_id("CVE-2019-1977");

  script_name(english:"Cisco Nexus 9000 Series Fabric Switches ACI Mode Border Leaf Endpoint Learning (CVE-2019-1977)");

  script_set_attribute(attribute:"synopsis", value:
"The remote OT asset is affected by a vulnerability.");
  script_set_attribute(attribute:"description", value:
"A vulnerability within the Endpoint Learning feature of Cisco Nexus
9000 Series Switches running in Application Centric Infrastructure
(ACI) mode could allow an unauthenticated, remote attacker to cause a
denial of service (DoS) condition on an endpoint device in certain
circumstances. The vulnerability is due to improper endpoint learning
when packets are received on a specific port from outside the ACI
fabric and destined to an endpoint located on a border leaf when
Disable Remote Endpoint Learning has been enabled. This can result in
a Remote (XR) entry being created for the impacted endpoint that will
become stale if the endpoint migrates to a different port or leaf
switch. This results in traffic not reaching the impacted endpoint
until the Remote entry can be relearned by another mechanism.

This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.");
  # https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-nexus-aci-dos
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?9a5ce967");
  script_set_attribute(attribute:"solution", value:
"Refer to the vendor advisory.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/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:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2019-1977");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_cwe_id(371);

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/08/30");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/08/30");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/07/25");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:nx-os:12.3%281h%29");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:nx-os:13.1%282m%29");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:nx-os:13.1%282o%29");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:nx-os:13.1%282p%29");
  script_set_attribute(attribute:"generated_plugin", value:"former");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Tenable.ot");

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

  script_dependencies("tenable_ot_api_integration.nasl");
  script_require_keys("Tenable.ot/Cisco");

  exit(0);
}


include('tenable_ot_cve_funcs.inc');

get_kb_item_or_exit('Tenable.ot/Cisco');

var asset = tenable_ot::assets::get(vendor:'Cisco');

var vuln_cpes = {
    "cpe:/o:cisco:nx-os:12.3%281h%29" :
        {"versionEndIncluding" : "12.3%281h%29", "versionStartIncluding" : "12.3%281h%29", "family" : "NXOS"},
    "cpe:/o:cisco:nx-os:13.1%282m%29" :
        {"versionEndIncluding" : "13.1%282m%29", "versionStartIncluding" : "13.1%282m%29", "family" : "NXOS"},
    "cpe:/o:cisco:nx-os:13.1%282o%29" :
        {"versionEndIncluding" : "13.1%282o%29", "versionStartIncluding" : "13.1%282o%29", "family" : "NXOS"},
    "cpe:/o:cisco:nx-os:13.1%282p%29" :
        {"versionEndIncluding" : "13.1%282p%29", "versionStartIncluding" : "13.1%282p%29", "family" : "NXOS"}
};

tenable_ot::cve::compare_and_report(asset:asset, cpes:vuln_cpes, severity:SECURITY_WARNING);