According to its banner, the remote host is running OpenSSL version 1.1.0a. It is, therefore, affected by a remote code execution vulnerability in the read_state_machine() function in statem.c due to improper handling of messages larger than 16k. An unauthenticated, remote attacker can exploit this, via a specially crafted message, to cause a use-after-free error, resulting in a denial of service condition or possibly the execution of arbitrary code.
#
# (C) Tenable Network Security, Inc.
#
include("compat.inc");
if (description)
{
script_id(93787);
script_version("1.8");
script_set_attribute(attribute:"plugin_modification_date", value:"2023/08/08");
script_cve_id("CVE-2016-6309");
script_bugtraq_id(93177);
script_name(english:"OpenSSL 1.1.0a read_state_machine() Function Message Handling RCE");
script_summary(english:"Performs a banner check.");
script_set_attribute(attribute:"synopsis", value:
"The remote service is potentially affected by a remote code execution
vulnerability.");
script_set_attribute(attribute:"description", value:
"According to its banner, the remote host is running OpenSSL version
1.1.0a. It is, therefore, affected by a remote code execution
vulnerability in the read_state_machine() function in statem.c due to
improper handling of messages larger than 16k. An unauthenticated,
remote attacker can exploit this, via a specially crafted message, to
cause a use-after-free error, resulting in a denial of service
condition or possibly the execution of arbitrary code.");
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 1.1.0b or later.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C");
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:H/I:H/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-2016-6309");
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 and is owned by Tenable, Inc. or an Affiliate thereof.");
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' : "1.1.0a", 'fixed_version' : '1.1.0b'}];
vcf::openssl::check_version_and_report(app_info:app_info, constraints:constraints, severity:SECURITY_HOLE);