CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
SINGLE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:L/Au:S/C:N/I:P/A:N
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
EPSS
Percentile
17.3%
According to its self-reported version, Cisco IOS Software is affected by a vulnerability in the access control logic of the Secure Shell (SSH) server due to a missing check in the SSH server. An authenticated, remote attacker can exploit this, by providing valid credentials to access a device in order to open an SSH connection to an affected device with a source address belonging to a VRF instance, despite the absence of the ‘vrf-also’ keyword in the access-class configuration.
Please see the included Cisco BIDs and Cisco Security Advisory for more information.
Note that Nessus has not tested for this issue but has instead relied only on the application’s self-reported version number.
#TRUSTED 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
#
# (C) Tenable Network Security, Inc.
#
include('compat.inc');
if (description)
{
script_id(131727);
script_version("1.8");
script_set_attribute(attribute:"plugin_modification_date", value:"2021/01/14");
script_cve_id("CVE-2018-0484");
script_bugtraq_id(106560);
script_xref(name:"CISCO-BUG-ID", value:"CSCvk37852");
script_xref(name:"CISCO-SA", value:"cisco-sa-20190109-ios-ssh-vrf");
script_name(english:"Cisco IOS Software Secure Shell Connection on VRF (cisco-sa-20190109-ios-ssh-vrf)");
script_set_attribute(attribute:"synopsis", value:
"The remote device is missing a vendor-supplied security patch.");
script_set_attribute(attribute:"description", value:
"According to its self-reported version, Cisco IOS Software is affected by a vulnerability in the access control logic
of the Secure Shell (SSH) server due to a missing check in the SSH server. An authenticated, remote attacker can
exploit this, by providing valid credentials to access a device in order to open an SSH connection to an affected
device with a source address belonging to a VRF instance, despite the absence of the 'vrf-also' keyword in the
access-class configuration.
Please see the included Cisco BIDs and Cisco Security Advisory for more information.
Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
# https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190109-ios-ssh-vrf
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?efbc26fd");
script_set_attribute(attribute:"see_also", value:"https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvk37852");
script_set_attribute(attribute:"solution", value:
"Upgrade to the relevant fixed version referenced in Cisco bug ID(s) CSCvk37852.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:N/I:P/A:N");
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:L/UI:N/S:U/C:N/I:H/A:N");
script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2018-0484");
script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
script_set_attribute(attribute:"vuln_publication_date", value:"2019/01/10");
script_set_attribute(attribute:"patch_publication_date", value:"2016/01/09");
script_set_attribute(attribute:"plugin_publication_date", value:"2019/12/06");
script_set_attribute(attribute:"plugin_type", value:"combined");
script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:ios");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"CISCO");
script_copyright(english:"This script is Copyright (C) 2019-2021 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("cisco_ios_version.nasl");
script_require_keys("Host/Cisco/IOS/Version");
exit(0);
}
include('cisco_workarounds.inc');
include('ccf.inc');
product_info = cisco::get_product_info(name:'Cisco IOS');
version_list = make_list(
'12.2(60)EZ12',
'15.3(3)JA1n',
'15.6(2)SP3b',
'15.7(3)M3',
'15.8(3)M',
'15.8(3)M0a',
'15.8(3)M0b'
);
workarounds = make_list(CISCO_WORKAROUNDS['no_workaround']);
workaround_params = make_list();
reporting = make_array(
'port' , product_info['port'],
'severity' , SECURITY_WARNING,
'version' , product_info['version'],
'bug_id' , 'CSCvk37852'
);
cisco::check_and_report(
product_info:product_info,
workarounds:workarounds,
reporting:reporting,
vuln_versions:version_list
);
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
SINGLE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:L/Au:S/C:N/I:P/A:N
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
EPSS
Percentile
17.3%