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.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Changed

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00252.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
Cisco Cisco IOS XR Software unknown
Version Status Constraints
6.5.29 affected —
7.0.1 affected —
6.5.26 affected —
6.5.25 affected —
6.5.28 affected —
6.5.90 affected —
7.1.1 affected —
7.0.90 affected —
6.7.1 affected —
7.0.2 affected —
7.1.15 affected —
7.2.1 affected —
7.1.2 affected —
6.7.2 affected —
7.0.11 affected —
7.0.12 affected —
7.0.14 affected —
7.1.25 affected —
7.2.12 affected —
7.3.1 affected —
7.1.3 affected —
6.7.3 affected —
7.4.1 affected —
7.2.2 affected —
6.7.4 affected —
6.5.31 affected —
7.3.15 affected —
7.3.16 affected —
6.8.1 affected —
7.4.15 affected —
6.5.32 affected —
7.3.2 affected —
7.5.1 affected —
7.4.16 affected —
7.3.27 affected —
7.6.1 affected —
7.5.2 affected —
7.8.1 affected —
7.6.15 affected —
7.5.12 affected —
7.8.12 affected —
7.3.3 affected —
7.7.1 affected —
6.8.2 affected —
7.3.4 affected —
7.4.2 affected —
6.7.35 affected —
6.9.1 affected —
7.6.2 affected —
7.5.3 affected —
7.7.2 affected —
6.9.2 affected —
7.9.1 affected —
7.10.1 affected —
7.8.2 affected —
7.5.4 affected —
6.5.33 affected —
7.8.22 affected —
7.7.21 affected —
7.9.2 affected —
7.3.5 affected —
7.5.5 affected —
7.11.1 affected —
7.9.21 affected —
7.10.2 affected —
24.1.1 affected —
7.6.3 affected —
7.3.6 affected —
7.5.52 affected —
7.11.2 affected —
24.2.1 affected —
24.1.2 affected —
24.2.11 affected —
24.3.1 affected —
24.4.1 affected —
24.2.2 affected —
7.8.23 affected —
7.11.21 affected —
24.2.20 affected —
24.3.2 affected —
24.4.10 affected —
6.5.35 affected —
25.1.1 affected —
24.4.2 affected —
24.3.20 affected —
24.4.15 affected —
25.2.1 affected —
6.5.351 affected —
25.1.2 affected —
24.3.30 affected —
25.3.1 affected —
6.5.352 affected —
24.4.30 affected —
24.2.21 affected —
25.4.1 affected —
25.2.2 affected —
25.2.15 affected —
7.2.0 affected —
7.0.0 affected —
25.2.30 affected —
6.5.353 affected —
26.1.1 affected —
25.1.30 affected —
25.3.15 affected —
26.2.100 affected —
25.4.2 affected —
26.2.1 affected —
25.4.30 affected —
26.1.2 affected —
25.4.201 affected —
26.2.101 affected —

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

No data.

Project Subscriptions

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-iosxr-qg64NcM cve-icon cve-icon
History

Wed, 02 Sep 2026 16:30:00 +0000

Type Values Removed Values Added
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.
Title Cisco IOS XR Software Security Hardening Release: September 2026
Weaknesses CWE-691
References
Metrics cvssV3_1

{'score': 8.6, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: cisco

Published:

Updated: 2026-09-02T17:58:59.117Z

Reserved: 2025-10-08T11:59:15.403Z

Link: CVE-2026-20276

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-09-02T17:17:32.957

Modified: 2026-09-02T19:23:13.660

Link: CVE-2026-20276

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-03T11:30:03Z

Weaknesses