CVE-2026-20279 CRITICAL

CVE-2026-20279: Cisco IOS XR Software Security Hardening Release: September 2026

Vendor Cisco
Product Cisco IOS XR Software
Weakness CWE-284
Published September 2, 2026
Last update September 3, 2026
View on NVD All CVEs

CVSS base score

9.8/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

What the vulnerability does

01Description

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XR Software engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20279 are related to improper access control issues that are grouped under the Common Weakness Enumeration (CWE) CWE-284.

Key dates

02Disclosure timeline

September 2, 2026 CVE published
September 3, 2026 Record updated

Related vulnerabilities

04Related CVE

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