Cisco ASA Uncontrolled Resource Consumption (CVE-2020-3196)

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

include('compat.inc');

if (description)
{
  script_id(506157);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/07");

  script_cve_id("CVE-2020-3196");
  script_xref(name:"CEA-ID", value:"CEA-2020-0042");

  script_name(english:"Cisco ASA Uncontrolled Resource Consumption (CVE-2020-3196)");

  script_set_attribute(attribute:"synopsis", value:
"The remote OT asset is affected by a vulnerability.");
  script_set_attribute(attribute:"description", value:
"A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer
Security (TLS) handler of Cisco Adaptive Security Appliance (ASA)
Software and Cisco Firepower Threat Defense (FTD) Software could allow
an unauthenticated, remote attacker to exhaust memory resources on the
affected device, leading to a denial of service (DoS) condition. The
vulnerability is due to improper resource management for inbound
SSL/TLS connections. An attacker could exploit this vulnerability by
establishing multiple SSL/TLS connections with specific conditions to
the affected device. A successful exploit could allow the attacker to
exhaust the memory on the affected device, causing the device to stop
accepting new SSL/TLS connections and resulting in a DoS condition for
services on the device that process SSL/TLS traffic. Manual
intervention is required to recover an affected device.

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-asa-ssl-vpn-dos-qY7BHpjN
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?6420bb6e");
  script_set_attribute(attribute:"solution", value:
"Refer to the vendor advisory.");
  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:C/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-2020-3196");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_cwe_id(400);

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/05/06");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/05/06");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/06");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:adaptive_security_appliance_software:9");
  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) 2026 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:adaptive_security_appliance_software:9.6" :
        {"versionEndExcluding" : "9.6.4.40", "versionStartIncluding" : "9.6", "family" : "CiscoFirepower"},
    "cpe:/o:cisco:adaptive_security_appliance_software:9.8" :
        {"versionEndExcluding" : "9.8.4.20", "versionStartIncluding" : "9.8", "family" : "CiscoFirepower"},
    "cpe:/o:cisco:adaptive_security_appliance_software:9.9" :
        {"versionEndExcluding" : "9.9.2.66", "versionStartIncluding" : "9.9", "family" : "CiscoFirepower"},
    "cpe:/o:cisco:adaptive_security_appliance_software:9.10" :
        {"versionEndExcluding" : "9.10.1.37", "versionStartIncluding" : "9.10", "family" : "CiscoFirepower"},
    "cpe:/o:cisco:adaptive_security_appliance_software:9.12" :
        {"versionEndExcluding" : "9.12.3.2", "versionStartIncluding" : "9.12", "family" : "CiscoFirepower"},
    "cpe:/o:cisco:adaptive_security_appliance_software:9.13" :
        {"versionEndExcluding" : "9.13.1.7", "versionStartIncluding" : "9.13", "family" : "CiscoFirepower"}
};

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