According to its banner, the version of OpenSSH running on the remote host is prior to version 5.9. Such versions are affected by multiple denial of service vulnerabilities :
A denial of service vulnerability exists in the gss-serv.c ‘ssh_gssapi_parse_ename’ function. A remote attacker may be able to trigger this vulnerability if gssapi-with-mic is enabled to create a denial of service condition via a large value in a certain length field.
(CVE-2011-5000)
On FreeBSD, NetBSD, OpenBSD, and other products, a remote, authenticated attacker could exploit the remote_glob() and process_put() functions to cause a denial of service (CPU and memory consumption).
(CVE-2010-4755)
#
# (C) Tenable, Inc.
#
include("compat.inc");
if (description)
{
script_id(17703);
script_version("1.8");
script_set_attribute(attribute:"plugin_modification_date", value:"2024/03/27");
script_cve_id("CVE-2010-4755","CVE-2011-5000");
script_bugtraq_id(54114, 68757);
script_name(english:"OpenSSH < 5.9 Multiple DoS");
script_summary(english:"Checks OpenSSH banner version");
script_set_attribute(attribute:"synopsis", value:
"The SSH server on the remote host has multiple denial of service
vulnerabilities.");
script_set_attribute(attribute:"description", value:
"According to its banner, the version of OpenSSH running on the remote
host is prior to version 5.9. Such versions are affected by multiple
denial of service vulnerabilities :
- A denial of service vulnerability exists in the
gss-serv.c 'ssh_gssapi_parse_ename' function. A remote
attacker may be able to trigger this vulnerability if
gssapi-with-mic is enabled to create a denial of service
condition via a large value in a certain length field.
(CVE-2011-5000)
- On FreeBSD, NetBSD, OpenBSD, and other products, a
remote, authenticated attacker could exploit the
remote_glob() and process_put() functions to cause a
denial of service (CPU and memory consumption).
(CVE-2010-4755)");
script_set_attribute(attribute:"see_also", value:"http://cxsecurity.com/research/89");
script_set_attribute(attribute:"see_also",value:"http://site.pi3.com.pl/adv/ssh_1.txt");
script_set_attribute(attribute:"solution", value:"Upgrade to OpenSSH 5.9 or later.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:N/I:N/A:P");
script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
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:"2010/07/07");
script_set_attribute(attribute:"patch_publication_date", value:"2011/09/06");
script_set_attribute(attribute:"plugin_publication_date", value:"2011/11/18");
script_set_attribute(attribute:"plugin_type", value:"remote");
script_set_attribute(attribute:"cpe", value:"cpe:/a:openbsd:openssh");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Denial of Service");
script_copyright(english:"This script is Copyright (C) 2023-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("openssh_detect.nbin");
script_require_keys("installed_sw/OpenSSH", "Settings/PCI_DSS");
script_require_ports("Services/ssh", 22);
exit(0);
}
include('backport.inc');
include('vcf.inc');
include('vcf_extras.inc');
# OpenSSH is only affected on certain OSes.
if (!get_kb_item("Settings/PCI_DSS")) exit(0, "PCI-DSS compliance checking is not enabled.");
var port = get_service(svc:'ssh', default:22, exit_on_fail:TRUE);
var app_info = vcf::openssh::get_app_info(app:'OpenSSH', port:port);
vcf::check_all_backporting(app_info:app_info);
var constraints = [
{'fixed_version' : '5.9'}
];
vcf::openssh::check_version_and_report(app_info:app_info, constraints:constraints, severity:SECURITY_WARNING);