CVE-2026-20279: Improper Access Control in Cisco Cisco IOS XR Software
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.
CVSS v3.1
Score 9.8critical
Affected software
Cisco
Cisco IOS XR Software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Cisco IOS XR Software contains an improper access control vulnerability (CVE-2026-20279) discovered through an internal security review. This vulnerability is categorized under CWE-284 and affects numerous exact versions of Cisco IOS XR Software. The CVSS 3.1 vector indicates network attack vector, low attack complexity, no privileges required, no user interaction, unchanged scope, and high impact on confidentiality, integrity, and availability. Cisco has released software hardening updates addressing this and other internally discovered vulnerabilities.
Potential Impact
Successful exploitation of this vulnerability could allow an unauthenticated attacker to gain unauthorized access, potentially leading to full compromise of confidentiality, integrity, and availability of the affected Cisco IOS XR devices. Given the critical CVSS score of 9.8, the impact is severe and could disrupt network operations or expose sensitive data.
Mitigation Recommendations
Cisco has released software hardening updates that address this vulnerability. Users should apply the official fixes provided by Cisco for the affected versions. Since this is not a cloud service, remediation depends on deploying these updates. Patch status is confirmed by Cisco's advisory indicating the availability of fixes.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- cisco
- Date Reserved
- 2025-10-08T11:59:15.403Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6a9850dcacd9273b4977c51b
Added to database: 09/02/2026, 16:37:48 UTC
Last enriched: 09/22/2026, 03:20:03 UTC
Last updated: 10/18/2026, 18:48:18 UTC
Views: 281
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.