Vulnerability identifier: #VU16928
Vulnerability risk: Low
CVSSv3.1: 4.6 [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]
CVE-ID:
CWE-ID:
CWE-119
Exploitation vector: Network
Exploit availability: No
Vulnerable software:
Cisco IOS
Operating systems & Components /
Operating system
Vendor: Cisco Systems, Inc
Description
The vulnerability allows a remote attacker to bypass security restrictions on the target system.
The vulnerability exists in the access control logic of the Secure Shell (SSH) server due to a missing check in the SSH server. A remote unauthenticated attacker can open an SSH connection to an affected Cisco IOS or IOS XE device with a source address belonging to a VRF instance and forward the instance despite the absence of the vrf-also keyword in the access-class configuration.
Mitigation
The vulnerability has been fixed in the versions 16.6.5, 16.6(4.12), 15.8(3.1s)M, 15.8(3)M1.
Vulnerable software versions
Cisco IOS: 16.6.2 - 16.6.4
External links
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190109-ios-ssh-vrf
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.