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-2026-20274 are related to improper resource control issues that are grouped under the Common Weakness Enumeration (CWE) CWE-664.
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
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 45 · as of 3 November 2026
- CWE
- CWE-664
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.