Vulnerability Name:

CVE-2018-0484 (CCN-155317)

Assigned:2017-11-27
Published:2019-01-09
Updated:2019-10-09
Summary:A vulnerability in the access control logic of the Secure Shell (SSH) server of Cisco IOS and IOS XE Software may allow connections sourced from a virtual routing and forwarding (VRF) instance despite the absence of the vrf-also keyword in the access-class configuration. The vulnerability is due to a missing check in the SSH server. An attacker could use this vulnerability to open an SSH connection to an affected Cisco IOS or IOS XE device with a source address belonging to a VRF instance. Once connected, the attacker would still need to provide valid credentials to access the device.
CVSS v3 Severity:6.5 Medium (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N)
5.7 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): High
Availibility (A): None
5.3 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)
4.6 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): Low
Availibility (A): None
CVSS v2 Severity:4.0 Medium (CVSS v2 Vector: AV:N/AC:L/Au:S/C:N/I:P/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Authentication (Au): Single_Instance
Impact Metrics:Confidentiality (C): None
Integrity (I): Partial
Availibility (A): None
5.0 Medium (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:P/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): Partial
Availibility (A): None
Vulnerability Type:CWE-noinfo
Vulnerability Consequences:Bypass Security
References:Source: MITRE
Type: CNA
CVE-2018-0484

Source: BID
Type: Third Party Advisory, VDB Entry
106560

Source: XF
Type: UNKNOWN
cisco-cve20180484-sec-bypass(155317)

Source: CCN
Type: Cisco Security Advisory cisco-sa-20190109-ios-ssh-vrf
Cisco IOS and IOS XE Software Secure Shell Connection on VRF Vulnerability

Source: CISCO
Type: Vendor Advisory
20190109 Cisco IOS and IOS XE Software Secure Shell Connection on VRF Vulnerability

Vulnerable Configuration:Configuration 1:
  • cpe:/o:cisco:ios:16.6.2:*:*:*:*:*:*:*
  • OR cpe:/o:cisco:ios:16.6.4:*:*:*:*:*:*:*

    • Configuration CCN 1:
  • cpe:/o:cisco:ios_software:*:*:*:*:*:*:*:*
  • OR cpe:/o:cisco:ios_xe_software:*:*:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    BACK
    cisco ios 16.6.2
    cisco ios 16.6.4
    cisco ios software *
    cisco ios xe software *