Vulnerability record · CVE-2026-20276 · published 2 September 2026

CVE-2026-20276: Cisco ios xr vulnerability

Cisco · Ios Xr

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-2026-20276 are related to insufficient control flow management issues that are grouped under the Common Weakness Enumeration (CWE) CWE-691.

8.6 CVSS 3.1 High EPSS 0.27% · top 83.1% CWE-691 · CWE-691

8.6CVSS 3.1 base score

0.27%EPSS exploitation probability, 30 days

NoNot in CISA KEV

1Affected product versions listed by NVD

2References

18 Sep 2026Last modified by NVD

Description

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

Ios Xr Cisco

References

Link	Tags
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-iosxr-qg64NcM	Vendor Advisory
https://www.cve.org/Media/News/item/blog/2026/06/16/Preserving-Vulnerability-Level-Identification	Not Applicable

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-20276), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.