CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
NONE
Availability Impact
NONE
AV:N/AC:M/Au:N/C:P/I:N/A:N
EPSS
Percentile
58.7%
The remote Cisco security appliance uses a default host key that is shared among all installations of the product. An unauthenticated, remote attacker with knowledge of the private key can impersonate other devices or perform a man-in-the-middle attack between this host and other virtual security appliances.
#
# (C) Tenable Network Security, Inc.
#
include("compat.inc");
if (description)
{
script_id(84500);
script_version("1.9");
script_cvs_date("Date: 2019/11/22");
script_cve_id("CVE-2015-4217");
script_xref(name:"CISCO-BUG-ID", value:"CSCus29681");
script_xref(name:"IAVA", value:"2015-A-0136");
script_xref(name:"CISCO-BUG-ID", value:"CSCuu95676");
script_xref(name:"CISCO-BUG-ID", value:"CSCuu96601");
script_xref(name:"CISCO-SA", value:"cisco-sa-20150625-ironport");
script_name(english:"Cisco Ironport Security Appliance Default Host Key Vulnerability");
script_summary(english:"Checks if the remote host responds with a known key.");
script_set_attribute(attribute:"synopsis", value:
"The remote security appliance is missing a vendor-supplied patch.");
script_set_attribute(attribute:"description", value:
"The remote Cisco security appliance uses a default host key that is
shared among all installations of the product. An unauthenticated,
remote attacker with knowledge of the private key can impersonate
other devices or perform a man-in-the-middle attack between this host
and other virtual security appliances.");
# https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20150625-ironport
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?fab9519e");
script_set_attribute(attribute:"solution", value:
"Apply the relevant update referenced in Cisco Security Advisory
cisco-sa-20150625-ironport.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:N");
script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2015-4217");
script_set_attribute(attribute:"exploitability_ease", value:"No exploit is required");
script_set_attribute(attribute:"exploit_available", value:"false");
script_set_attribute(attribute:"vuln_publication_date", value:"2015/06/25");
script_set_attribute(attribute:"patch_publication_date", value:"2015/06/25");
script_set_attribute(attribute:"plugin_publication_date", value:"2015/07/02");
script_set_attribute(attribute:"plugin_type", value:"remote");
script_set_attribute(attribute:"cpe", value:"cpe:/a:cisco:content_security_management_virtual_appliance");
script_set_attribute(attribute:"cpe", value:"cpe:/a:cisco:email_security_virtual_appliance");
script_set_attribute(attribute:"cpe", value:"cpe:/a:cisco:web_security_virtual_appliance");
script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:asyncos");
script_set_attribute(attribute:"default_account", value:"true");
script_set_attribute(attribute:"stig_severity", value:"I");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"CISCO");
script_copyright(english:"This script is Copyright (C) 2015-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("ssh_detect.nasl");
script_require_ports("Services/ssh", 22);
exit(0);
}
include("global_settings.inc");
include("audit.inc");
include("misc_func.inc");
port = get_service(svc:'ssh', default:22, exit_on_fail:TRUE);
host_key = get_kb_item("SSH/publickey/ssh-rsa/" + port);
if (empty_or_null(host_key))
host_key = get_kb_item("SSH/publickey/ssh-dsa/" + port);
if (empty_or_null(host_key))
exit(0, "Nessus was unable to obtain the host's key.");
default_keys = make_list(
"AAAAB3NzaC1yc2EAAAADAQABAAABAQCmkCwuBsBk12gtO2niJivv8bZncl44dOq09SyVuPbTL8RfoKona01g0cyfiwdnqBmBW7P2CA+5V3gq0/rGOfJ5TpElTLK/F8od8zF5K0mhSE20FPCbTVigR4m2xij/fKI8h+jJMbYPEV82yIIGGG+802Q7pGR0p4CU0a9yNqFNhr52egJNWVj98O3jM8vdFw1eTogEEa7zkQO/YF1EQ9V+q5U1le0DbZ5vmgFIt/7nOersnnszYMdywPPWRtIJJveI8hbhfC9HZ7CQIXWPiYv1rrjGBdDX4LonE4kIMU3CCf/a4DH+rX4FGtKYdxiPlJS2TxV8Nv1PcIovj/aYdYlf",
"AAAAB3NzaC1yc2EAAAADAQABAAABAQCqz7uUNZKJDvXz44PeixU/bQsJ3pziZP0FpO1AS4ANvOJ7aOsWMfhzvXnimMsRfMVPARoHTn6Q5EsW2jkgWo0qa6/HMlhc/196zEmvnIrNuvYvQiwHzIAzm3MlhZLbWYGUtPl4L1pQUsn4GAKc9OYqyub6kYBeKvNj3N+kGpTs6oXHpmy4qC8LsNOHwVREPN3/6q4D3tqGkO+x0LKXoIXxB/bHgelPbCdRSxKOnizudu6Gjj5UVLGhDU1Oy1bfzbvzNQG7bFx0ueAL/2FVVplICcj5fTHm9yqUcl/3We6TgaFAtL/lPqGpI1y0UAEvfNpmDp+wAztZAOY6FRA03cPh",
"AAAAB3NzaC1yc2EAAAADAQABAAABAQDG3Yd4tfLqaj+Cu7D0BgwnYsexDSlb+loUfPalvfGPgWjF+HQiorytLRKVEf8SBHRjMiXX901gKPSKfyFvoAzMHlR8LtO0c9B1SoDdenWgRiYzu1G1z4baEq2YOSpt8yLrVc27jrdR1gf0NAXxHXQTKT5YfpvjEuDr25azKGQAHIe+17U70ruwcPeBGO/RGQ+aHn58DGbO8GKRsxhTZjO13SdgmpDoCQbWvMzgAqEPZNJqbZy7PA/3wKtpu5yYTFKUSmkBfOvCrHmA+POXl+F2Brg2/S7J4kbivacfNDEn5rlGuiY/On6E2Zj3nkI5x5r1OCasuh9cLdx++2/2bAf/"
);
vuln = FALSE;
foreach default_key (default_keys)
{
if (default_key == host_key)
{
vuln = TRUE;
break;
}
}
if (vuln)
{
if (report_verbosity > 0)
{
report =
'\nNessus was able to verify that the remote host uses the following' +
'\ndefault SSH public key :' +
'\n Key : ' + host_key +
'\n';
security_warning(port:port, extra:report);
}
else security_warning(port);
}
else audit(AUDIT_HOST_NOT, "affected");