OpenSSL 1.0.2i CRL Handling NULL Pointer Dereference DoS

#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(93786);
  script_version("1.8");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/08/21");

  script_cve_id("CVE-2016-7052");
  script_bugtraq_id(93171);

  script_name(english:"OpenSSL 1.0.2i CRL Handling NULL Pointer Dereference DoS");
  script_summary(english:"Performs a banner check.");

  script_set_attribute(attribute:"synopsis", value:
"The remote service is affected by a denial of service vulnerability.");
  script_set_attribute(attribute:"description", value:
"According to its banner, the remote host is running OpenSSL version
1.0.2i. It is, therefore, affected by a denial of service
vulnerability in x509_vfy.c due to improper handling of certificate
revocation lists (CRLs). An unauthenticated, remote attacker can
exploit this, via a specially crafted CRL, to cause a NULL pointer
dereference, resulting in a crash of the service.");
  script_set_attribute(attribute:"see_also", value:"https://www.openssl.org/news/secadv/20160926.txt");
  script_set_attribute(attribute:"solution", value:
"Upgrade to OpenSSL version 1.0.2j or later.");
  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:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2016-7052");

  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:"2016/09/26");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/09/26");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/09/28");

  script_set_attribute(attribute:"plugin_type", value:"combined");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:openssl:openssl");
  script_set_attribute(attribute:"agent", value:"all");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Web Servers");

  script_copyright(english:"This script is Copyright (C) 2016-2023 Tenable Network Security, Inc.");

  script_dependencies("openssl_version.nasl", "openssl_nix_installed.nbin", "openssl_win_installed.nbin");
  script_require_keys("installed_sw/OpenSSL");

  exit(0);
}

include('vcf.inc');
include('vcf_extras_openssl.inc');

var app_info = vcf::combined_get_app_info(app:'OpenSSL');

vcf::check_all_backporting(app_info:app_info);

var constraints = [{ 'min_version' : "1.0.2i", 'fixed_version' : '1.0.2j'}];

vcf::openssl::check_version_and_report(app_info:app_info, constraints:constraints, severity:SECURITY_WARNING);