Usage of static SSH host key in Cisco Umbrella Virtual Appliance

1) Use of Hard-coded Cryptographic Key

EUVDB-ID: #VU62464

Risk: High

CVSSv4.0: 6.3 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2022-20773

CWE-ID: CWE-321 - Use of Hard-coded Cryptographic Key

Exploit availability: No

Description

The vulnerability allows a remote attacker to impersonate the virtual appliance.

The vulnerability exists due to the presence of a static SSH host key. A remote attacker can perform a man-in-the-middle (MitM) attack on an SSH connection to the Umbrella VA.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Cisco Umbrella Virtual Appliance: 3.0.0 - 3.3.1

CPE2.3

• cpe:2.3:a:cisco_systems:cisco_umbrella_virtual_appliance:3.0.0:*:*:*:*:*:*:*
• cpe:2.3:a:cisco_systems:cisco_umbrella_virtual_appliance:3.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:cisco_systems:cisco_umbrella_virtual_appliance:3.0.2:*:*:*:*:*:*:*

External links

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-uva-static-key-6RQTRs4c
https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwa11399

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.