CVE-2017-6679

mediumpriority · track · 26EPSS 0.003 · 27 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.34% (27th) EPSS

CVSS 6 · medium

Is it mine?

4 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-27

The Cisco Umbrella Virtual Appliance Version 2.0.3 and prior contained an undocumented encrypted remote support tunnel (SSH) which auto initiated from the customer's appliance to Cisco's SSH Hubs in the Umbrella datacenters. These tunnels were primarily leveraged for remote support and allowed for authorized/authenticated personnel from the Cisco Umbrella team to access the appliance remotely and obtain full control without explicit customer approval. To address this vulnerability, the Umbrella Virtual Appliance version 2.1.0 now requires explicit customer approval before an SSH tunnel from the VA to the Cisco terminating server can be established.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedCisco Umbrella Insights Virtual Appliancecisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com

cvss

Technical severity, 0–10. One row per scoring source.

6.4

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.06mediumAV:L/AC:H/Au:S/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 1.5 · impact 10

v3.16.4mediumCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 0.5 · impact 5.9

v3.06.4mediumCVSS:3.0/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:Hsecondary · Cisco PSIRT US

v3.16.4mediumAV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.15.9mediumCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-254US

affected products (4)

Products and version ranges known to be affected.

Cisco Cisco Umbrella Insights Virtual Applianceall versionscisco_csafUS
n/a Cisco Umbrella Virtual Appliance Version 2.0.3 and prior≤ Cisco Umbrella Virtual Appliance Version 2.0.3 and priorenisa_euvdEU
Cisco Systems Inc. Cisco Umbrella≤ 2.1.0fstec_bduRU
cisco umbrella virtual appliance< 2.1.0nvdUScpe:2.3:a:cisco:umbrella_virtual_appliance:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

cisco-sa-umbrella-tunnel-gJw5thgECisco Umbrella Virtual Appliance Undocumented Support Tunnel Vulnerability2023-08-16csaf · cisco_csafUS
A vulnerability in the remote support feature of Cisco Umbrella Virtual Appliance could allow an authenticated, remote attacker to obtain full control of an affected device. This vulnerability is due to an undocumented support mechanism that is present on the product. An attacker could exploit this vulnerability by obtaining privileges sufficient to access the remote support tunnel. A successful exploit could allow the attacker to access the appliance remotely and obtain full control without explicit customer approval. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. Cisco Umbrella originally published this advisory in 2017 on a different site that has since been archived.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cisco_csaf nvd NVD CVE.org MITRE

published 2017-12-01modified 2026-06-22

references (15)

External citations — patches, advisories, analysis.

scry

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