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-2026-20277 are related to protection mechanism failure issues that are grouped under the Common Weakness Enumeration (CWE) CWE-693.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact Low

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 0.00219.

Exploitation none

Automatable yes

Technical Impact partial

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.

Vendors Products
Cisco Subscribe
Ios Xr Software Subscribe

Project Subscriptions

Vendors Products
Cisco Subscribe
Ios Xr Software Subscribe
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

Thu, 03 Sep 2026 15:45:00 +0000

Type Values Removed Values Added
First Time appeared Cisco
Cisco ios Xr Software
Vendors & Products Cisco
Cisco ios Xr Software

Thu, 03 Sep 2026 08:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

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-2026-20277 are related to protection mechanism failure issues that are grouped under the Common Weakness Enumeration (CWE) CWE-693.
Title Cisco IOS XR Software Security Hardening Release: September 2026
Weaknesses CWE-693
References
Metrics cvssV3_1

{'score': 8.2, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H'}

Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: cisco

Published:

Updated: 2026-09-02T17:58:59.278Z

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

Link: CVE-2026-20277

cve-icon Vulnrichment

Updated: 2026-09-02T17:56:53.444Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-09-02T17:17:33.110

Modified: 2026-09-03T16:37:52.170

Link: CVE-2026-20277

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-03T15:30:05Z

Weaknesses