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-2026-20276 are related to insufficient control flow management issues that are grouped under the Common Weakness Enumeration (CWE) CWE-691.
Affected products
cisco: ios xr
References2
- sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAd… Vendor Advisory
- www.cve.org/Media/News/item/blog/2026/06/16/Preserving-Vulnerab… Not Applicable
Metrics
- CVSS 3.1
-
8.6
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 40 · as of 3 November 2026
- CWE
- CWE-691
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