CVE-2026-76466

Cisco Expressway Series Remote Code Execution Vulnerability

Published Oct 21, 2026 CVSS 3.1 · 9.8 Critical EPSS < 1% KEV · Not listed

Description

A vulnerability in the database service feature of Cisco Expressway Series could allow an unauthenticated, remote attacker with network access to a Cisco Expressway device to execute arbitrary operating system commands as root.

This vulnerability is due to the use of persistent cookies. Additionally, there is insufficient validation of client certificates when the TLS Verify Mode is set to Enabled for clustering, which means that client certificates are not validated. An attacker with possession of the cookies could exploit this vulnerability by connecting to the database service and invoking specific remote procedure call (RPC) commands. A successful exploit could allow the attacker to execute arbitrary commands as root on the underlying operating system of an affected device.
Note: Cisco Expressway Series refers to Cisco Expressway Core (Expressway-C) devices and Cisco Expressway Edge (Expressway-E) devices.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Cisco

Cisco TelePresence Video Communication Server (VCS) Expressway

unknown

Version	Status	Constraints
`X8.11.2`	affected	—
`X8.6`	affected	—
`X8.11.3`	affected	—
`X8.2.2`	affected	—
`X8.8.3`	affected	—
`X8.11.0`	affected	—
`X12.5.2`	affected	—
`X8.1.1`	affected	—
`X8.9`	affected	—
`X12.5.1`	affected	—
`X12.5.6`	affected	—
`X8.7.3`	affected	—
`X12.6.0`	affected	—
`X8.11.1`	affected	—
`X8.5`	affected	—
`X8.9.1`	affected	—
`X8.10.2`	affected	—
`X8.8.2`	affected	—
`X8.5.3`	affected	—
`X8.1`	affected	—
`X8.9.2`	affected	—
`X8.11.4`	affected	—
`X12.5.4`	affected	—
`X8.8.1`	affected	—
`X8.2.1`	affected	—
`X8.5.1`	affected	—
`X8.6.1`	affected	—
`X8.1.2`	affected	—
`X8.8`	affected	—
`X8.10.0`	affected	—
`X12.5.3`	affected	—
`X8.10.1`	affected	—
`X12.5.7`	affected	—
`X8.10.3`	affected	—
`X8.7.1`	affected	—
`X8.2`	affected	—
`X12.5.8`	affected	—
`X8.7`	affected	—
`X8.5.2`	affected	—
`X12.5.9`	affected	—
`X12.5.0`	affected	—
`X8.10.4`	affected	—
`X8.7.2`	affected	—
`X12.5.5`	affected	—
`X12.6.1`	affected	—
`X12.6.2`	affected	—
`X12.6.3`	affected	—
`X12.6.4`	affected	—
`X12.7.0`	affected	—
`X12.7.1`	affected	—
`X14.0.0`	affected	—
`X14.0.1`	affected	—
`X14.0.2`	affected	—
`X14.0.3`	affected	—
`X14.0.4`	affected	—
`X14.0.5`	affected	—
`X14.0.6`	affected	—
`X14.0.7`	affected	—
`X14.0.8`	affected	—
`X14.2.0`	affected	—
`X14.0.9`	affected	—
`X14.2.1`	affected	—
`X14.2.2`	affected	—
`X14.0.11`	affected	—
`X14.2.5`	affected	—
`X14.0.10`	affected	—
`X14.2.6`	affected	—
`X14.2.7`	affected	—
`X14.3.0`	affected	—
`X14.3.1`	affected	—
`X14.3.2`	affected	—
`X14.3.3`	affected	—
`X15.0.0`	affected	—
`X14.3.4`	affected	—
`X14.3.5`	affected	—
`X15.0.1`	affected	—
`X15.0.2`	affected	—
`X15.0.3`	affected	—
`X14.3.6`	affected	—
`X15.2.0`	affected	—
`X15.2.1`	affected	—
`X15.2.2`	affected	—
`X15.2.3`	affected	—
`X14.3.7`	affected	—
`X15.2.4.`	affected	—
`X15.2.4`	affected	—
`X15.3.0`	affected	—
`X15.3.1`	affected	—
`X15.3.2`	affected	—
`X15.4.0`	affected	—
`X15.5.0`	affected	—
`X15.5.1`	affected	—
`X15.5.2`	affected	—
`X15.5.3`	affected	—

No data.

Vendor Product Versions

Cisco

Expressway Series

Version	Status	Scheme	Platform
`X8.11.2`	affected	generic	—
`X8.6`	affected	generic	—
`X8.11.3`	affected	generic	—
`X8.2.2`	affected	generic	—
`X8.8.3`	affected	generic	—
`X8.11.0`	affected	generic	—
`X12.5.2`	affected	generic	—
`X8.1.1`	affected	generic	—
`X8.9`	affected	generic	—
`X12.5.1`	affected	generic	—
`X12.5.6`	affected	generic	—
`X8.7.3`	affected	generic	—
`X12.6.0`	affected	generic	—
`X8.11.1`	affected	generic	—
`X8.5`	affected	generic	—
`X8.9.1`	affected	generic	—
`X8.10.2`	affected	generic	—
`X8.8.2`	affected	generic	—
`X8.5.3`	affected	generic	—
`X8.1`	affected	generic	—
`X8.9.2`	affected	generic	—
`X8.11.4`	affected	generic	—
`X12.5.4`	affected	generic	—
`X8.8.1`	affected	generic	—
`X8.2.1`	affected	generic	—
`X8.5.1`	affected	generic	—
`X8.6.1`	affected	generic	—
`X8.1.2`	affected	generic	—
`X8.8`	affected	generic	—
`X8.10.0`	affected	generic	—
`X12.5.3`	affected	generic	—
`X8.10.1`	affected	generic	—
`X12.5.7`	affected	generic	—
`X8.10.3`	affected	generic	—
`X8.7.1`	affected	generic	—
`X8.2`	affected	generic	—
`X12.5.8`	affected	generic	—
`X8.7`	affected	generic	—
`X8.5.2`	affected	generic	—
`X12.5.9`	affected	generic	—
`X12.5.0`	affected	generic	—
`X8.10.4`	affected	generic	—
`X8.7.2`	affected	generic	—
`X12.5.5`	affected	generic	—
`X12.6.1`	affected	generic	—
`X12.6.2`	affected	generic	—
`X12.6.3`	affected	generic	—
`X12.6.4`	affected	generic	—
`X12.7.0`	affected	generic	—
`X12.7.1`	affected	generic	—
`X14.0.0`	affected	generic	—
`X14.0.1`	affected	generic	—
`X14.0.2`	affected	generic	—
`X14.0.3`	affected	generic	—
`X14.0.4`	affected	generic	—
`X14.0.5`	affected	generic	—
`X14.0.6`	affected	generic	—
`X14.0.7`	affected	generic	—
`X14.0.8`	affected	generic	—
`X14.2.0`	affected	generic	—
`X14.0.9`	affected	generic	—
`X14.2.1`	affected	generic	—
`X14.2.2`	affected	generic	—
`X14.0.11`	affected	generic	—
`X14.2.5`	affected	generic	—
`X14.0.10`	affected	generic	—
`X14.2.6`	affected	generic	—
`X14.2.7`	affected	generic	—
`X14.3.0`	affected	generic	—
`X14.3.1`	affected	generic	—
`X14.3.2`	affected	generic	—
`X14.3.3`	affected	generic	—
`X15.0.0`	affected	generic	—
`X14.3.4`	affected	generic	—
`X14.3.5`	affected	generic	—
`X15.0.1`	affected	generic	—
`X15.0.2`	affected	generic	—
`X15.0.3`	affected	generic	—
`X14.3.6`	affected	generic	—
`X15.2.0`	affected	generic	—
`X15.2.1`	affected	generic	—
`X15.2.2`	affected	generic	—
`X15.2.3`	affected	generic	—
`X15.2.4.`	affected	generic	—
`X15.2.4`	affected	generic	—
`X15.3.0`	affected	generic	—
`X15.3.1`	affected	generic	—
`X15.3.2`	affected	generic	—
`X15.4.0`	affected	generic	—
`X15.5.0`	affected	generic	—
`X15.5.1`	affected	generic	—
`X15.5.2`	affected	generic	—
`X15.5.3`	affected	generic	—

Remediation

No solution or workaround provided in the CVE record

Tracking

Advisories

No advisories available

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.417% probability within 30 days)

Exploitation none

Automatable yes

Technical Impact total

References

Link	Providers
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-vcs-static-cred-hr7EWZ8t

History

Oct 23, 2026 12:45 AM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Oct 22, 2026 11:00 AM First appearance in the feed. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Cisco Cisco expressway Series
Vendors & Products		Cisco Cisco expressway Series

Oct 21, 2026 5:15 PM Description updated. Title updated. Weaknesses updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		A vulnerability in the database service feature of Cisco Expressway Series could allow an unauthenticated, remote attacker with network access to a Cisco Expressway device to execute arbitrary operating system commands as root. This vulnerability is due to the use of persistent cookies. Additionally, there is insufficient validation of client certificates when the TLS Verify Mode is set to Enabled for clustering, which means that client certificates are not validated. An attacker with possession of the cookies could exploit this vulnerability by connecting to the database service and invoking specific remote procedure call (RPC) commands. A successful exploit could allow the attacker to execute arbitrary commands as root on the underlying operating system of an affected device. Note: Cisco Expressway Series refers to Cisco Expressway Core (Expressway-C) devices and Cisco Expressway Edge (Expressway-E) devices.
Title		Cisco Expressway Series Remote Code Execution Vulnerability
Weaknesses		CWE-798
References		https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-vcs-static-cred-hr7EWZ8t
Metrics		cvssV3_1 `{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}`