SSL/TLS: Known Compromised/Static Certificate Detection

# SPDX-FileCopyrightText: 2021 Greenbone AG
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-only

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.147122");
  script_version("2026-04-17T15:51:27+0000");
  script_tag(name:"last_modification", value:"2026-04-17 15:51:27 +0000 (Fri, 17 Apr 2026)");
  script_tag(name:"creation_date", value:"2021-11-10 02:22:55 +0000 (Wed, 10 Nov 2021)");
  script_tag(name:"cvss_base", value:"5.0");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:P/I:N/A:N");
  script_tag(name:"severity_vector", value:"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N");
  script_tag(name:"severity_origin", value:"NVD");
  script_tag(name:"severity_date", value:"2017-09-12 15:56:00 +0000 (Tue, 12 Sep 2017)");

  # nb: Unlike other VTs we're using the CVEs line by line here for easier addition of new CVEs / to
  #     avoid too large diffs when adding a new CVE.
  script_cve_id("CVE-2015-6358",
                "CVE-2015-7255",
                "CVE-2015-7256",
                "CVE-2015-7276",
                "CVE-2015-8251",
                "CVE-2015-8260"
               );

  script_tag(name:"qod_type", value:"remote_vul");

  script_tag(name:"solution_type", value:"Mitigation");

  script_name("SSL/TLS: Known Compromised/Static Certificate Detection");

  script_category(ACT_GATHER_INFO);

  script_copyright("Copyright (C) 2021 Greenbone AG");
  script_family("SSL and TLS");
  script_dependencies("gb_ssl_tls_cert_details.nasl");
  script_mandatory_keys("ssl/cert/avail", "ssl_tls/port");

  script_tag(name:"summary", value:"The remote SSL/TLS service is using an SSL/TLS certificate which
  is known to be compromised/static (e.g. known private keys, used by malware, etc).");

  script_tag(name:"vuldetect", value:"The script checks the SSL/TLS SHA-1 fingerprint of the SSL/TLS
  certificate of the remote SSL/TLS service against a list of known compromised/static ones.");

  script_tag(name:"impact", value:"An attacker could use this for man-in-the-middle (MITM) attacks,
  accessing sensible data and other attacks.");

  script_tag(name:"affected", value:"A wide range of devices from vendors like Actiontec, Cisco,
  D-Link Systems, General Electric, Huawei Technologies, NetComm Wireless Limited, Sierra Wireless,
  Technicolor, Ubiquiti Networks, ZTE Corporation and ZyXEL are known to be affected.");

  script_tag(name:"solution", value:"Replace the SSL/TLS certificate with a trusted/clean one.");

  script_xref(name:"URL", value:"https://web.archive.org/web/20210921041640/https://www.fireeye.com/blog/threat-research/2013/03/md5-sha1.html");
  script_xref(name:"URL", value:"https://web.archive.org/web/20210302170420/https://www.fireeye.com/blog/threat-research/2017/06/behind-the-carbanak-backdoor.html");
  script_xref(name:"URL", value:"https://cloud.google.com/blog/topics/threat-intelligence/behind-the-carbanak-backdoor/");
  script_xref(name:"URL", value:"https://web.archive.org/web/20200114095203/https://code.google.com/archive/p/littleblackbox/");
  script_xref(name:"URL", value:"https://www.kb.cert.org/vuls/id/566724");
  script_xref(name:"URL", value:"https://sec-consult.com/blog/detail/house-of-keys-industry-wide-https/");
  script_xref(name:"URL", value:"https://sec-consult.com/blog/detail/house-of-keys-9-months-later-40-worse/");
  script_xref(name:"URL", value:"https://github.com/sec-consult/houseofkeys");
  script_xref(name:"URL", value:"https://web.archive.org/web/20180610144949/https://www.sec-consult.com/download/ssh_host_keys.html");
  script_xref(name:"URL", value:"https://web.archive.org/web/20180610144950/https://sec-consult.com/download/certificates.html");

  exit(0);
}

include("byte_func.inc");
include("list_array_func.inc");
include("misc_func.inc");
include("mysql.inc");
include("ssl_tls_bad_fingerprints.inc");
include("ssl_funcs.inc");
include("host_details.inc");

if (!port = tls_ssl_get_port())
  exit(0);

sni_ctx = tls_get_sni_context_key();

cert = get_server_cert(port: port);

bad_keys = make_list_unique(ssl_bad_fingerprints);

if (cert) {
  obj = cert_open(cert);
  if (!obj)
    exit(0);

  fingerprint = cert_query(obj, "fpr-sha-1");
  cert_close(obj);
  if (!fingerprint)
    exit(99);

  if (in_array(search: fingerprint, array: bad_keys, part_match: FALSE)) {

    # nb:
    # - Store the reference from this one to gb_ssl_tls_cert_details.nasl to show a cross-reference
    #   within the reports
    # - We don't want to use get_app_* functions as we're only interested in the cross-reference here
    register_host_detail(name: "detected_by", value: "1.3.6.1.4.1.25623.1.0.103692"); # gb_ssl_tls_cert_details.nasl
    register_host_detail(name: "detected_at", value: port + "/tcp");

    key = get_kb_item("HostDetails/SSLInfo/" + port + "/" + sni_ctx);
    if (!key)
      key = get_kb_item("HostDetails/SSLInfo/" + port);
    report = 'The following SSL/TLS certificate is known to be compromised:\n' +
             cert_summary(key: "HostDetails/Cert/" + key + "/");
    security_message(port: port, data: report);
    exit(0);
  }
}

exit(99);