CVE-2026-20279

critical

Description

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.

References

https://www.securityweek.com/cisco-warns-of-unpatched-secure-email-flaws-patches-critical-switch-vulnerabilities/

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-iosxr-qg64NcM

Details

Source: Mitre, NVD

Published: 2026-09-02

Updated: 2026-09-03

Risk Information

CVSS v2

Base Score: 10

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Severity: Critical

CVSS v3

Base Score: 9.8

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

Severity: Critical

EPSS

EPSS: 0.00284