Vulnerability · Published Oct 21, 2026 · Assigned by cisco
CVE-2026-76491Cisco Expressway Series Software Hardening Release: October 2026 - Denial of Service Vulnerabilities
High 7.5
In plain English
A high-severity security flaw in Cisco TelePresence Video Communication Server (VCS) Expressway from Cisco. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 30% of all known vulnerabilities).
Official description
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Expressway Series software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-76491 are related to issues concerning reachable assertions that are grouped under the Common Weakness Enumeration (CWE) Base CWE-617.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Cisco TelePresence Video Communication Server (VCS) Expressway | X8.11.2X8.6X8.11.3X8.2.2X8.8.3X8.11.0X12.5.2X8.1.1 |
Weakness: CWE-617 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H