Status: UPDATED | Advisory ID: CVE-2026-20271
| CVE | CVE-2026-20271 |
| CVSS Score / Version | 8.6 (High) / CVSS v3.1 |
| Updated | 2026-09-20 |
| CVSS Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
| CVSS Prose | attack vector is network; attack complexity is low; privileges required is none; user interaction is none; scope is changed; confidentiality impact is none; integrity impact is none; availability impact is high. |
| Affected products | Cisco IOS XE |
| Classified as | CWE-691 (Insufficient Control Flow Management) |
| Exploitation prediction (EPSS) | 0.47% probability of exploitation in the next 30 days (38% percentile) -- FIRST.org's EPSS model. |
| Vendor | Product | Affected Versions | Patch Status |
|---|---|---|---|
| Cisco | IOS XE |
| Subsystems | Industrial Network - Routers/Firewalls |
| Sectors | Critical Manufacturing, Energy, Transportation Systems, Water and Wastewater Systems |
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XE 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-2026-20271 are related to insufficient control flow management issues that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-691.
Monitor Cisco's web page for any future patch releases. See vendor advisory link below.